[AnswerKey] UPSC Prelims-2021: Science & Sports- Solutions & Strategy for Next Year & “D” Option ki Guessmaster-giri

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  1. Science-tech= “D” Option Guess-mastergiriTM
    1. Trend analysis of the Sci-Tech questions in UPSC prelim exams?
    2. Was the paper more friendly towards the IIT-JEE/NEET crowd?
    3. “General Science observation” APOLOGISTs & their SAPNA Theory
    4. Utility of theHindu newspaper?
    5. Utility of current affairs pdf files?
    6. Prelims-2022 Strategy: Science Theory
    7. Prelims-2022 Strategy: Science Current Affairs & Contemporary Affairs
    8. How to prepare Science for UPSC Mains-2022 (GSM3)?
  2. Science-Tech Answerkey: Physics & Chemistry MCQs from UPSC prelims 2021
  3. Science-Tech Answerkey: Public Health
    1. Private Answerkeys Differ in Sci-Tech
  4. PIN (Persons in News/ Sports/ Awards) MCQs from UPSC prelims 2021 including STRATEGY for 2022
    1. Private Answerkeys NOT Differ in Sports/PIN

Science-tech= “D” Option Guess-mastergiriTM

Since most students want  shortcuts without hard work, and e-learning thugs want pageviews and followers. So, they are peddling this new rule of “Guess-master GiriTM / meta keyword analysis that says:

“In science technology MCQs, if you cannot solve the answer, then simply tick “D” option.”

Let’s quickly check the validity of this:

Year No. of Science MCQs were “D” is the right Answer NET GAIN or NET LOSS?

=(correct*2m)-(incorrect*0.66)

2021 4 out of 11 MCQs =36% 4*2-(7*0.66)=+ 3.38 marks🤩
2020 7 out of 11 MCQ= 63%* (7*2)-(4*0.66)=+11.36🤩
2019 2 out of 11 MCQs = 19% -1.94😰
2018 5 out of 13 MCQs = 38% +4.72🤩
2017 2 out of 6 MCQs = 33% +1.36🤩
  • *For 2020 and 2021 exams, the official answer key is yet to be declared. For the remaining exams (2017 to 2019), I have used the official UPSC answer key.
  • Thus, if a candidate is unsure about a particular MCQ in science technology, and gives D as the answer, then overall he may gain a few marks, except the 2019 paper.
  • I do not like peddling this type of hacks/cheat codes/shortcuts. But I have mentioned this phenomenon here so that UPSC examiner can take cognizance of this matter and frame better quality of questions next year.
  • ✋and No, I donot make any claims that →
    • A) In future exams also this “Science = D Answer” will be equally useful OR that
    • B) You should stop studying science technology and engage in this type of shortcuts!

Trend analysis of the Sci-Tech questions in UPSC prelim exams?

[AnswerKey] UPSC Prelims-2021: Science & Sports- Solutions & Strategy for Next Year & “D” Option ki Guessmaster-giri

Science-Tech in 2015 to 2020 Prelim Papers 2021 Prelims: Continuity and change in the Science-Tech questions
2019 and 2020: 11 MCQ asked number of questions same (11), difficulty and Varity  also similar to 2020 paper.
Less MCQs from theory, more from contemporary issues Reverse: 6 from theory, 5 from non-theory.
2019 and 2020 Number of MCQs: Biotech > ICT > Physics 2021: Science Qs: Public Heath (5) > Chemistry (3) > Physics (2). Nothing from IT/Electronics.
-In 2019 paper: 5 science MCQs were one liner. i.e. Question and directly ABCD option given

-In 2020 paper: Only 3 science MCQs were ‘one liner’. Rest of them- Two statements, Three statements, Five statements given and you have to find the correct statements! So it was more time consuming and mentally exhaustive.

Similar to 2020 paper- only 3 MCQ were one liner. Remaining 8 MCQ had two to three statements each. and you have to find the correct statements! So it was more time consuming and mentally exhaustive.
-2019: Virus used to be a favorite topic. Asked about H1N1, Ebola, Zika etc

-2020: No Direct question on virus despite coronavirus!

Virus prem resurfaced.
2019 asked about

-Microbial pathogens drug resistance

-Hepatitis vaccine

-Even in past there have been questions related to biotechnology Medical Research such as CRISPR technology, gene silencing therapy  etc.

2020: ‘Pronuclear Transfer” for reproduction

2021

-Similar non-sense resurfaced with Adenovirus, Mitochondria 3 parent baby MCQ.

– 2019: ICT “service technology” asked: NFC, Project Loon, LIFI, LTE vs VOLTE

– 2020: Again asked about LIFI (VLC Technology)

Nothing from ICT
– 2015-19: Cyber security related organisations / provisions asked. Wannacry Ransomware, Digital signature

– 2020: Trend continued

NOTHING
– 2015-19: Asked about Electronics gadgets / technology like GPS, 3D printer, Internet of things (IoT), Augmented reality vs virtual reality, Wearable devices

– 2020: Asked about gadgets- Drones

Nothing from electronic gadgets.
– 2015-19: Sometimes asked about ISRO/India space satellite exploration related Qs such as IRNSS

– 2020: nothing from ISRO

NOTHING from ISRO.
– 2017: asked about ELISA. But it was a much easier because simply 1 word association asked “Elisa= Detecting gravitational waves”

– 2020: again asked, But this time in the much tougher manner.

This ELISA / space-gravity prem replaced with LIGHT Year Prem.
– 2015-19: Questions from the pure physics such as -light and gravity, string theory, Magnetic field of the earth, Blackholes etc. = pure Class-11-12 Physics book type theory.

– 2020: Application / research based science technology asked. So, command over Class-11-12 Physics theory, not very useful.

2021: middle path. Little bit more theory than 2020. So, yes somewhat friendly to IIT/NEET/Science stream walla.
– 2019: Ask about Caveman fossils  (आदिमानव के अवशेषों के बारे में)

– 2020: Nothing

– 2021: Nothing from Fossil Tamasha.

– God forbid, if tomorrow UPSC asks a question about dinosaur fossils (Since the Hindu writes  50 articles on each every year)  then, some of the e-Learning channels will create a separate “subject” out of it “Dinosaur fossils Compilation”, Just like they have invented a new subject “PIB Compilation”!

Was the paper more friendly towards the IIT-JEE/NEET crowd?

  • Nature of the many science-tech questions was such that research level topics were asked. Not directly given in books. Even private answer keys differ/vary depending on which research paper they use for solving the MCQ.
  • Nonetheless, some MCQs help the IIT-JEE/NEET/Class 11-12-PCM/Science walla crowd in 50:50 elimination.
  • When the UPSC Prelim result will be out, many of the failed-candidates will blame “IIT/NEET/B.Sc Agriculture -walle took my seat.” But you (non-Science/Engineer walla) should also introspect on what other mistakes you had made in the paper by yourself & fix it in the next attempt.
  • Besides, do not expect competitive exams to be full of justice and unbiased towards every stream. The UPSC is not going to give the ready-made things on a platter to you. You will have to work for it (And hope that luck is also on your side!)
  • So, if a Commerce / Arts / MBA student is thinking, “I’ll ignore Sci-Tech and make up the deficit through Environment, Polity, Economy, History-Culture.” Well, then he’s making a mistake because those (non-Science) topics are not getting any easier.

“General Science observation” APOLOGISTs & their SAPNA Theory

  • Nehru apologists cannot find any fault in Prime Minister Nehru’s policies.
  • Modi apologists cannot find any fault in Prime Minister Modi’s policies.
  • Similarly UPSC’s “General Science observation” APOLOGISTs, typically say the following: “Because we use the water pump sets and therefore UPSC asked a tricky question from whether solar energy can be used for submersible pump or not?…It is all about general observation from your day today life around you. Similar for Pressure cooker question and water polarity and LED/Sodium Lamp question- इसलिए आपको सपना आ जाना चाहिए था की ये सब पूछा जानेवाला है. IQ nhi EQ chaahiye…” 
  • …. Bhai Given such a large Syllabus of UPSC, who has the time to bring his head out of the books and PDF files, to go around the world and observe everything like Sheldon Cooper from Big Bang Theory sitcom!!?
  • So I do not subscribe to their theories.

Utility of theHindu newspaper?

  • The scene is similar to the agriculture questions asked in UPSC Prelims 2020
  • some questions may be solved but it requires you to go back to the newspapers of 2016 (e.g. Mitochondria 3 parent baby) which is normally not possible for candidates at present. So for answers, I am not crediting theHindu आपको सपना आ जाना चाहिए था की 2016-2017 के  अख़बार से ये सब पूछा जानेवाला है.
  • Other questions such as ACE2, Tricolasan could be solved either from IndianExpress or from theHindu. So, it’s not compulsory to read IndianExpress

Utility of current affairs pdf files?

  • While they cover the ISRO/science technology in great detail in their monthly free current affair PDF files but nothing could be solved except- ‘ACE2’ MCQ. and you could have solve this even from daily IndianExpress reading.
  • For remaining questions, A) either the material was not available, or B) it was not giving the particular information which is asked in the MCQ.
  • At the same time, it doesn’t mean you should stop reading it all together. You should glance over it just to be familiar with what has been happening around. Save the time and trouble of not having to maintain your own notes out of newspapers.
  • ✋But at the same time you should not be spending a disproportionate amount of your time in current affairs.

Prelims-2022 Strategy: Science Theory

  • Way back in 2013-14, UPSC asked very silly and easy questions from science like name of diseases caused by Vitamin deficiency. So, NCERT (Class7-10) + LucentGK type combo would have sufficed.
  • But in recent exams, hardly any direct questions are coming from there
  • For example, Newton’s laws, laws of electricity, friction and optics, various uses of basic chemicals ….nothing is asked in recent years. Therefore, going through bulky General Studies Manuals = poor cost benefit.
  • Yes you should be familiar with those Basic concepts (Newton’s laws etc.) because They may indirectly help you in elimination of some wrong options And also in the other exams such as CDS,CAPF, StatePSC,SSC.
  • but in the NCERT Class10-11-12: you should focus more on study of chapters / topics having relevance with environment, agriculture, public health, biotech, space and ICT/communication.
  • Class 11 and 12 NCERT biology and chemistry books are required even for the solving environment flora fauna related questions so you should not neglect them

Prelims-2022 Strategy: Science Current Affairs & Contemporary Affairs

  • While preparing science Current/Contemporary affairs, the target areas should be: Environment, Agriculture, Public Health, Biotech, ICT/communication and Space.
  • Within Space, first priority to ISRO than NASA, then other countries and lastly to the randomly discovered stars and planets.
  • Go through the science technology questions asked in the previous years. Because
    • 1) sometimes the themes / wrong options are again asked (e.g. CAS9). And
    • 2) at least it gives you a rough idea in defining the boundary of your syllabus and preparation for science-tech.
  • Contemporary Affairs (ie. topics older than one year): Book such as Ravi Agrahari Unacademy Booklet or any other similar books from science-tech.
  • Current Affairs (i.e. 1/1/2019 onwards): Free PDF compilations- whichever catches your fancy (VisionIAS, IASparliament, Unacademy Articulate etc).
    • While such PDF compilations have given very little utility / benefit in Prelim-2021’s Science-Tech portion, as if UPSC examination had carefully monitored them and carefully avoided asking anything given it.
    • But, the opposite strategy that,” I will prepare my super speciality notes on science technology from newspapers directly!” = poor cost:benefit, because:
    • 1) For majority of the topics in your handmade notes will overlap with those freely available PDF compilations.
    • 2) To think like a UPSC examiner, first you will have to go through all PDF compilations then compare them with the newspaper, then identify which topic is not covered there, so you will make a super speciality note on it. This is impracticable and complete waste of time. Because such minutes things from Sci-tech are not asked in Mains. Besides cutoff is never 200/200 marks and your Prelim score is not counted in the final selection.
  • Read theHindu / IndianExpress daily: Make notes from it Only If you’ve a very compelling reason to do so, e.g. This quotation or case study is very useful for the mains/essay/ethics/optional paper; or This news-item from my graduation subject / homeState/ Hobby / Employer-Company may be asked in an interview.

How to prepare Science for UPSC Mains-2022 (GSM3)?

  • Mains General Studies Paper 3 (GSM3): Topic wise past questions & strategy for Science Tech has already been given in the following article: Click Me.
  • To conclude, there is no rocket science or secret formula to crack the science questions in IAS prelims. You prepare what you can, and then focus on the other subjects. जितना खुद से पढ़ सकते हो वह पढ़ो. फिर दूसरे विषयों की तैयारी करो. पूरा दिन इसको लेकर मत बैठे रहो. ✋

Anyways let’s now solve the science technology questions asked in UPSC Prelims 2021.

BTW, Sports MCQ also solved in this webpage.

Science-Tech: Physics & Chemistry MCQs from UPSC prelims 2021


[CSP21-SET-C] Q.21) Water can dissolve more substances than any other liquid because

  1. a) it is dipolar in nature 
  2. b) it is a good conductor of heat
  3. c) it has high value of specific heat
  4. d) it is an oxide of hydrogen

Difficulty : Medium 🧐 to Tough🥵

Type: Theory 📚

Explanation:

  • NCERT Class11 Chemistry: The polar nature of water makes it a very good solvent for ionic and partially ionic compounds;
  • Water molecules have a polar arrangement of the oxygen and hydrogen atoms—one side (hydrogen) has a positive electrical charge and the other side (oxygen) had a negative charge. This allows the water molecule to become attracted to many other different types of molecules. Therefore, Correct Answer is “A”.

📚 Source(s):

🎲 GuessMaster-GiriTM: Partially Possible. Option B and C are dealing with heat which is not making much word Association with the dissolution. So we are 50:50 between A or D.


[CSP21-SET-C] Q.22) With reference to street-lighting, how do sodium lamps differ from LED lamps?

  1. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.
  2. As street-lights, sodium lamps have longer lifespan than LED lamps.
  3. The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street lighting.

Select the correct answer using the code given below: 

  1. a) 3 only
  2. b) 2 only
  3. c) 1 and 3 
  4. d) 1, 2 and 3

Difficulty : Tough 🥵

Type: Theory 📚

Explanation:

  • Sodium lamps provide 360 degree light emitting. Whereas,LED lights tend to direct light downward, rather than a full 360 degrees. → #1 is right.
  • HPS Lights have good lifespans – around 14,000 hours – though this is significantly less than LEDs. LEDs last longer than any light source commercially available on the market. → #2 is wrong.
  • Monochromatic light means that the light has a single wavelength. The LED light is not monochromatic because it is made up of different wavelengths, therefore is polychromatic. Often, a combination of wavelengths is used to create different colors. → #3 is right.
  • Therefore, Correct Answer is “C”: 1 and 3.

📚 Source(s):

🎲 GuessMaster-GiriTM: N/A


[CSP21-SET-C] Q.26) Which one of the following is a reason why astronomical distances are measured in light-years?

  1. a) Distances among stellar bodies do not change.
  2. b) Gravity of stellar bodies does not change.
  3. c) Light always travels in a straight line.
  4. d) Speed of light is always the same.

Difficulty : Tough 🥵 Multiple answers possible depending on which source you believe.

Type: Theory 📚

Explanation:

  • Cosmologists use the light year as a measuring tool because speed of light in empty space /vacuum never changes. It remains constant. So, “D” is right.

📚 Source(s):

🎲 GuessMaster-GiriTM: Possible. While All statements contain extreme words, So, Rule#1 not possible but GM-Rule#6: Sci-Tech= Blindly Tick “D/All Correct”.

✋Counter Arguments

  • NCERT Class11 Physics: 1) When a ray of light that travels obliquely from one transparent medium into another, it will change its direction in the second medium. → C is wrong. 2) The speed of light changes as it enters from one transparent medium to another. This event can be seen by Refraction. So #D is also wrong.
  • Counter Argument NCERT Class11 Geography → Ch.2: Light travels at a speed of 300,000 km/second. Considering this, the distance the light will travel in one year is taken to be one light year. Therefore, Correct Answer is D.
  • Thus, NCERT is not helping to get a single answer. So I have used a third party book on google.
  • Final Judge? UPSC Official Answer Key.

[CSP21-SET-C] Q.38)  In a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following?

  1. Area of the hole in the lid.
  2. Temperature of the flame
  3. Weight of the lid

Select the correct answer using the code given below.

  1. a) 1 and 2 Only
  2. b) 2 and 3 Only
  3. c) 1 and 3 Only
  4. d) 1, 2 and 3

Difficulty : Tough🥵

Type: Theory 📚

Explanation:

  • By increasing the surface pressure on the liquid inside the closed cooker we can raise the cooking temperature. This pressure can be adjusted by changing the weight placed on the top of the cooker lid. → #3 is right. 
  • The cooker lid is provided with the safety hole/valve so when the pressure crosses the safety limit, it prevents the cooker from bursting and causing an accident. #1 is not relevant for controlling temperature but safety of pressure. →#1 is wrong.
  • Therefore, Correct Answer is B] 2 and 3 only.
  • Counter-argument: #1 (size of hole) also matters in heating.So, #1 is also correct and Answer should be “D”. Final Judge? Wait for UPSC Answer Key.

📚 Source(s):

🎲 GuessMaster-GiriTM: Possible. GM-Rule#6: Sci-Tech= Blindly Tick “D/All Correct”.  (Assuming that D is the correct answer).


[CSP21-SET-C] Q.24) Bisphenol A (BPA) , a cause of concern, is a structural/key component in the manufacture of which of the following kinds of plastics?

  1. Low density polyethylene
  2. Polycarbonate
  3. Polyethylene terephthalate
  4. Polyvinyl chloride

Difficulty :  Tough🥵 [While NCERT textbook has mentioned this chemical but particular information asked in this MCQ, is not available in the book. Similarly newspapers and frequently wrote about the the harmful effect on health by this chemical but this particular information not available easily.]

Type: Theory 📚

Explanation:

  • BPA is a precursor to important plastics, primarily certain polycarbonates and epoxy resins, as well as some polysulfones and certain niche materials.
  • Therefore, option “B” is correct.
  • Anti Guessmaster. GM Rule#6: In science technology questions blindly tick “D/All Correct.” Then you’ll arrive at wrong answer.

📚 Source(s):

🎲 GuessMaster-GiriTM: ANTI Guessmaster Rule#6. if u blindly tick D then u get wrong answer.


[CSP21-SET-C] Q.25) Triclosan considered harmful when exposed to high levels for a long time, is most likely present in which of the following?

  1. Food preservatives
  2. Fruit-ripening substances
  3. Reused plastic containers
  4. Toiletries

Difficulty : Tough🥵

Type: Contemporary 🗞

Explanation:

  • Triclosan is a common ingredient found in many grooming products, including facial washes, toothpaste and deodorants. However, it is mainly found in antibacterial hand washes, soaps, gels, and household cleaners.
  • Therefore, correct option is “D”.

📚 Source(s):

🎲 GuessMaster-GiriTM: Yes Applicable. GM Rule#6: In science technology questions blindly tick “D/All Correct.” Then you’ll arrive at the right answer.

Science-Tech: Public Health


[CSP21-SET-C] Q.35) With reference to recent developments regarding ‘Recombinant Vector Vaccines’, consider the following statements:

  1. Genetic engineering is applied in the development of these vaccines.
  2. Bacteria and viruses are used as vectors.

Which of the statements given above is/are correct?

  1. 1 Only
  2. 2 Only
  3. Both 1 and 2
  4. Neither 1 nor 2

Difficulty : Medium🧐 to Tough🥵 While this type of vaccine was in newspapers but the particular information asked in MCQ requires further crosschecking from random websites.

Type: Current/Contemporary 🗞

Explanation:

  • Recombinant vector vaccines are bacteria or viruses that are genetically engineered to carry extra genes derived from a pathogen. So, both statements are right, Therefore, option “C” is correct.

📚 Source(s):

🎲 GuessMaster-GiriTM: ANTI Guessmaster. GM Rule#6: In science technology questions blindly tick “D/All Correct.” Then you’ll arrive at wrong answer


[CSP21-SET-C] Q.36) In the context of hereditary diseases, consider the following statements: 

  1. Passing on  mitochondrial diseases from parent to child can be prevented by mitochondrial replacement therapy either before or after in vitro fertilization of egg.
  2. A child inherits mitochondrial diseases entirely from mother and not from father.

Which of the statements given above is/are correct?

  1. 1 only
  2. 2 only
  3. Both 1 and 2
  4. Neither 1 nor 2

Difficulty : Tough🥵

Type: Contemporary 🗞 from a news item of 2016.

Explanation:

  • This is from the Three parent baby news topic from 2016. Basically the mother has faulty Mitochondrial DNA. so the baby will have a disease. So, to prevent it, you’ve to remove the mother’s egg’s nuclear material → transfer it to another woman’s egg, then fertilize that second woman’s egg with the father’s sperm. 
  • So, statement#1 is wrong Because This step has to be done before fertilization.
  • This disease comes because of mother. → #2 is right.
  • So, Final Answer “B” : 2 Only.

📚 Source(s):

  • Mrunal’s 5 years old article There is a infographic given which can help solving the question easily. But that is not to say candidate should have got a divine dream before the exam that it was going to be asked and this article was published in 2016 that is 5 years ago!
  • Ravi Agrahari Science and technology book has a passing mention but alone it does not help solve this question

🎲 GuessMaster-GiriTM: Anti-Guessmaster. Second Statement has extreme word so, it would be wrong as per Rule#1. But then you get the wrong answer. GM Rule#6: In science technology questions blindly tick “D/All Correct.” Then you’ll arrive at wrong answer


[CSP21-SET-C] Q.39)  Consider the following:

  1. Bacteria
  2. Fungi
  3. Virus

Which of the above can be cultured in artificial/synthetic medium?

  1. 1 and 2 Only
  2. 2 and 3 Only
  3. 1 and 3 Only
  4. 1, 2 and 3

Difficulty : Tough🥵

Type: Theory 📚

Explanation:

  • Media most commonly used for bacteria are nutrient agar. Option #1 correct.
  • Media most commonly used for fungi are potato dextrose agar and Sabouraud dextrose agar. Option #2 correct.
  • Viruses can’t be cultured in artificial medium due to lack of metabolic machinery of their own and depend totally on the host cell for replication. Option #3 is incorrect.
  • Therefore, the correct answer is “A”: 1 and 2 only.

📚 Source(s):

🎲 GuessMaster-GiriTM: Anti Guessmaster. GM Rule#6: In science technology questions blindly tick “D/All Correct.” Then you’ll arrive at wrong answer.


[CSP21-SET-C] Q.23) The term ‘ACE2’ is talked about in the context of 

  1. genes introduced in the genetically modified plants
  2. development of India’s own satellite navigation system
  3. radio collar for wildlife tracking
  4. spread of viral diseases 

Difficulty : Easy🤩 covered in newspapers.

Type: Current🗞 It had been in news in context of Corona.

Explanation:

  • The SARS-CoV-2 virus enters a human cell through ‘ACE2 receptors’, which are enzymes that generate small proteins that are useful for the cell.
  • Therefore, correct answer is “D”.

📚 Source(s):

🎲 GuessMaster-GiriTM: Yes Applicable. GM Rule#6: In science technology questions blindly tick “D/All Correct.” Then you’ll arrive at right answer, without studying anything.


[CSP21-SET-C] Q.40)   Consider the following statements:

  1. Adenoviruses have single-stranded DNA genomes whereas retroviruses have double-stranded DNA genomes.
  2. Common cold is sometimes caused by an adenovirus whereas AIDS is caused by a retrovirus.

Which of the statements given above is/are correct?

  1. 1 Only
  2. 2 Only
  3. Both 1 and 2
  4. Neither 1 nor 2

Difficulty : Tough🥵

Type: Theory 📚

Explanation:

  • Adenoviruses are double-stranded DNA genomes. Retroviruses are single-stranded RNA animal viruses that employ a double-stranded DNA intermediate for replication. Option #1 is incorrect.
  • Common cold is a symptom of adenovirus. The retrovirus known as human immunodeficiency virus (HIV) causes acquired immunodeficiency syndrome (AIDS) in humans. Option #2 is correct.
  • Therefore, correct option is “2”.

📚 Source(s):

🎲 GuessMaster-GiriTM: Anti Guessmaster. GM Rule#6: In science technology questions blindly tick “D/All Correct.” Then you’ll arrive at the wrong answer.

Private Answerkeys Differ in Sci-Tech

Some questions are subject to multiple interpretations. I can spend 20-30 more minutes to come up with a more accurate answer, but it is not the best use of my time. Because

  1. Ultimately the final judge is UPSC answer key. That will be published next year after the interview result is announced.
  2. Nothing is gained financially or fame-wise by proving my answerkey is more correct than other institutes.
  3. So, I acknowledge the existence of other institutes answer keys and I also acknowledge the possibility that in some MCQs my Answerkey could be wrong. (दूसरे कोचिंग संस्थानों की उत्तरकुंजी के अस्तित्व को मैं स्वीकार करता हूँ. और मैं इस संभावना का भी स्वीकार करता हूँ कि किसी कुछ प्रश्नों में हो सकता है उनका जवाब सही निकले, और मेरा जवाब गलत निकले. लेकिन जब तक यूपीएससी खुद से अधिकारिक उत्तरकुंजी प्रकाशित नहीं करता, इस पर और ज्यादा समय बर्बाद करने का मतलब नहीं)
Q-SETC KEYWORD Guessmaster “D” ARE ALL private AKEY SAME? Key Mru Key
VisionIAS
Key-
Insights
KEY
SHANKAR
KEY
IASBABA
CSP21Q025 Triclosan Yes✅ TRUE D D D D D
CSP21Q024 BPA ANTI😭 TRUE B B B B B
CSP21Q038 Pressure Cooker Yes✅ ✋FALSE B/D C C C A
CSP21Q021 Water dissolve Partial TRUE A A A A A
CSP21Q023 ACE2 Yes✅ TRUE D D D D D
CSP21Q035 Recombinant Vector Vaccines ANTI😭 TRUE C C C C C
CSP21Q036 Hereditary diseases ANTI😭 ✋FALSE B C B C C
CSP21Q040 Adenovirus,Retrovirus ANTI😭 TRUE B B B B B
CSP21Q039 Artifical/Synthetic Medium ANTI😭 ✋FALSE A A D A A
CSP21Q022 Sodium Lamps No❌ TRUE C C C C C
CSP21Q026 Astronomical distance Yes✅ TRUE D D D D D

PIN (Persons in News/ Sports/ Awards) MCQs from UPSC prelims 2021 including STRATEGY for 2022

  • After changing the Prelim-syllabus in 2011, UPSC head almost stop asking questions related to Persons in News/ Sports/ Awards. Furthermore, even if you had studied basic factoids, still it was not possible to solve the all the questions which were asked here.
  • What is the strategy for 2022? Well you should keep an eye on such news but Without excessive devotion of time or energy into it

[CSP21-SET-C] Q.6) Consider the following statements in respect of Bharat Ratna and Padma Awards:

  1. Bharat Ratna and Padma Awards are titles under the Article 18(1) of the Constitution of India.
  2. Padma Awards, which were instituted in the year 1954, were suspended only once.
  3. The number of Bharat Ratna Awards is restricted to a maximum of five in a particular year.

Which of the above statements are not correct?

  1. 1 and 2 Only
  2. 2 and 3 Only
  3. 1 and 3 Only
  4. 1, 2 and 3

Difficulty : Tough🥵 Especially the second and third statement required testing of factual memory

Type: Contemporary 🗞 [Event older than one year asked.]

Explanation:

  • Government has mentioned that Bharat Ratna and Padma Awards are not to be considered as titles under Article 18 (1). Statement #1 is incorrect.
  • Padma Awards, suspended twice, from July 1977 to January 1980 and from August 1992 to December 1995. Statement #2 is incorrect.
  • of Bharat Ratna Awards is restricted to a maximum three in a particular year. Statement #3 is incorrect.
  • We are required to find wrong statements. So, Answer is “D”: 1, 2 and 3- All are wrong.

📚 Source(s):

🎲 GuessMaster-GiriTM: Partially Applicable. Because #2 and #3 contain extreme words, So they should be wrong as per the GM Rule#1. And in this question we are required to find the wrong statements.


[CSP21-SET-C] Q.8) Consider the following statements in respect of the Laureus World Sports Award which was instituted in the year 2000:

  1. American golfer Tiger Woods was the first winner of this award.
  2. The award has been received mostly by ‘Formula One’ players so far.
  3. Roger Federer received this award the maximum number of times compared to others.

Which of the above statements are correct?

  1. 1 and 2 Only
  2. 2 and 3 Only
  3. 1 and 3 Only
  4. 1, 2 and  3

Difficulty : Tough🥵 Not possible to memorize so many things

Type: Contemporary 🗞 [Because it is asking events older than 1 year]

Explanation:

  • Tiger Woods was the first winner of this award. Statement #1 is correct. So, Answer could be A / C / D.
  • The awards were received mostly by ‘Tennis’ players. Statement #2 is incorrect. Thus A,B, D are eliminated & we are left with only option.
  • Therefore, option “C” is correct.

📚 Source(s):

🎲 GuessMaster-GiriTM: Anti-Guessmaster because statement 1 and 3 contain extreme words, yet they are right!


[CSP21-SET-C] Q.9) Consider the following statements in respect of the 32nd Summer Olympics:

  1. The Official Motto for this Olympics is ‘A New World’.
  2. Sport Climbing, Surfing, Skateboarding, Karate and Baseball are included in this Olympics.

Which of the above statements is/are correct?

  1. 1 Only
  2. 2 Only
  3. Both 1 and 2
  4. Neither 1 nor 2

Difficulty : Tough🥵

Type: Current 🗞

Explanation:

  • Statement #1 is incorrect because the official motto was “United by Emotion”.
  • Six new sports will be contested this year at the Tokyo Olympics – baseball, softball, karate, skateboarding, sport climbing, and surfing – the most since 1920, when 11 new sports were added to the mix. Only statement #2 is correct.
  • Therefore, the correct option is “B”.

📚 Source(s):

🎲 GuessMaster-GiriTM: N/A


[CSP21-SET-C] Q.10) Consider the following statements in respect of the ICC World Test Championship:

  1. The finalists were decided by the number of matches they won.
  2. New Zealand was ranked ahead of England because it won more matches than England.

Which of the above statements is/are correct?

  1. 1 Only
  2. 2 Only
  3. Both 1 and 2
  4. Neither 1 nor 2

Difficulty : Tough🥵 Candidates cannot be expected to memorize such microscopic details about sports. Besides UPSC was traditionally (before 2011) was in habit of asking non-cricket sports questions. So one could never have invested so much time in preparation of cricket related general knowledge

Type:Current 🗞

Explanation:

  • As per the current regulations WTC league standings would be determined by the percentage of points (PCT) earned by teams. PCT is the percentage of points won out of the total number of points contested by each team.
  • Percentage of Points available method was taken into consideration for finalists due to COVID 19 pandemic. Statement #1 is incorrect.
  • New Zealand was ranked ahead of England because of more percentage points after win against Pakistan. Statement #2 is incorrect.
  • Therefore, correct option is “D”.

📚 Source(s):

🎲 GuessMaster-GiriTM: N/A

Private Answerkeys NOT Differ in Sports/PIN

All private answerkeys showing same answers.

Indian History Freedom Struggle Pratik Nayak

19 Comments on “[AnswerKey] UPSC Prelims-2021: Science & Sports- Solutions & Strategy for Next Year & “D” Option ki Guessmaster-giri”

    1. Mitochondrial Diseases and treatment had recently resurfaced in the Hindu and I could recollect it.So It should considered as current rather than contemporary

      1. Like how recent? I know it’s almost an impossible to answer but can you remember the approximate month or the range of months in which you saw it?

    2. True. It can be done after fertilization too. Thats why it is also called pronuclear technology. and Pro nuclear technology was asked in 2020 also. So, yeh toh padh ke jaana thha.

  1. Sir, pressure cooker question is already a debated one, nonetheless I’d like to add my 2 cents to your explanation. The question is about which of the following will affect the temperature of the food inside the cooker. Theory says by increasing the pressure inside the vessel we change the boiling point of water thereby it stays in the liquid state at higher temperature which decreases the time required to cook. So essentially the question is about which of the following affect the ‘pressure’ of the cooker. Hence i believe ‘D’ is a better option. In your explanation you are eliminating the statement because the size of hole will alter the pressure not the temperature is theoretically inconsistent.

  2. Sirji there are two types of Mitochondrial inheritance. 1st statement is also true. Please review the answer.

  3. The temperature at which food is cooked will depend on the pressure inside the cooker. Weight of the lid will affect the pressure inside the cooker only if the weight of the lid is supported by the air inside the cooker i.e only if the lid is free to slide up or down. But the lid of pressure cooker is not held free but held firmly when the Cooker is locked. So statement 3. Weight of the lid must be wrong.

  4. Sir, in pressure cooker question, Shouldn’t option 2 be wrong.
    Temperature of flame will only help in reaching the boiling point quicker. Its not going to change the boiling point.

  5. Literally laughed out when I saw that WTC and Olympics question. RIP those who stopped watching cricket and Olympics to focus on exams 😬

  6. Sir, In Q.26 “D” is surely the right answer because the rest three are factually wrong.
    A. Distance among stellar bodies is continously increasing because of expansion of space between them.(Metric Expansion)
    B. Gravity of stellar bodies can change. For ex. when a star dies its gravity reduces considerably.
    C. Light does not always travels in a straight line, even in a vacuum. It has been proven that gravity can bend the light’s path. Funfact, the movie “Gravity” is entirely based on this concept only.(https://astronomy.com/magazine/ask-astro/2019/09/how-does-gravity-affect-photons-that-is-bend-light-if-photons-have-no-mass)
    D. Speed of light is not always the same, it changes sharply with change in the medium.
    BUT, the speed of light is CONSTANT in a vacuum (not even effected by gravity). And that is where all the stellar bodies are present, in a vacuum. That is why all astronomical distances are measured in light years.

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