UPSC Prelims 2022 Q31-40: Common Sense & Logic Wins

This is Part 4 of the Sherlocking Prelims 2022 analysis, and it walks through UPSC Prelims 2022 questions 31 to 40 (Set A). The core lesson is simple: you clear Prelims with two ingredients only, revised basic sources and common sense. Across these ten questions Neil Sir shows how to identify when a question has not come from any standard source and how to crack it with logical reasoning, word association and a feel for how UPSC sets its options.

Key takeaways

• Every Prelims question fits one of three buckets: straight from a basic source, a source plus common sense, or pure logical reasoning. Recognising the bucket fast is half the battle.
• In this exam an overview of how things work is more rewarding than in-depth knowledge. Confidence to attempt comes from having analysed previous papers exhaustively before the exam.
• For unfamiliar technical terms, use word association: break the term into keywords and pick the option that matches all of them.
• UPSC rarely fabricates statements. Vague, non-extreme positive statements (using "can", "help") tend to be correct; negative qualifiers like "cannot" are red flags.
• The well-known, simplest fact is often the one made incorrect. Eliminate it and you frequently arrive at the answer without knowing the harder trivia.
• A question is not made hard by its subject but by how the options are set. The same fact can be easy or difficult depending on framing.
• Chasing 100-page compilations of obscure keywords is neither possible nor desirable; revise basics and practise the reasoning instead.

The three buckets: how to read any Prelims question

Before solving, Neil Sir reiterates the foundation of the whole series. Stick to basic sources and revise them repeatedly, then trust common sense. The moment you see a question, slot it into one of three categories:

• It has come directly from a standard source.
• It has come from a source but needs a little application of common sense.
• It is purely a logical reasoning question.

Most of Q31-40 fell into the third bucket. Once you accept that the information in the statement itself is enough to solve it, the initial paranoia of "I have not read this" disappears and you can attempt with confidence.

Positive statements and coherent options (Q31-Q33)

These three questions on open-source digital platforms, Web 3.0 and Software as a Service (SaaS) were all solved without recall.

• Q31 (open-source platforms): Neil Sir could not actively recall which applications were built on open source, so he reasoned from an overview of how government works. Government pushes digitisation and prefers open source to increase inclusivity, and he could find no reason to eliminate any of the four options, so he confidently marked the "all" option, which was correct.
• Q32 (Web 3.0): Two insights solved it. First, all the statements were positive. Second, the statements were coherent, so if one is true the others flow from it. If Web 3.0 lets people control their own data, it follows that it is operated by users collectively, and blockchain itself is about decentralisation. All three hung together, so the "all correct" option was right.
• Q33 (SaaS): Again three positive statements with no strong reason to negate, and the email examples sounded legitimate. Customising the interface, accessing data on mobile devices and email as a service all work in tandem, so the "all" option was correct once more.

The pattern: when statements are positive, non-extreme and mutually consistent, and you have no strong reason to negate them, lean towards accepting them.

Word association for unfamiliar terms (Q34 and Q35)

When a term is one you have genuinely never heard, do not freeze. Break it into keywords and test each option against all of them.

• Q34 (Fractional Orbital Bombardment System): Neil Sir had not heard of it, so he extracted three keywords, fractional, orbital and bombardment system. He then scanned every option for an essence matching all three. Only option C, where a missile is put into a stable orbit and then deorbits over the target, captured all three (missile maps to bombardment, orbit to orbital, deorbiting to the fractional aspect). It was correct.
• Q35 (qubit): A simpler case. Even without studying the topic, "qubit" intuitively associates with quantum computing, so the relevant option was a confident pick. Correct.

Reading how UPSC sets the options (Q36-Q40)

The later questions show that the framing of options, not the topic, decides difficulty.

• Q36 (biofilms): Three positive statements using the word "can" (on medical implants, on food, exhibiting antibiotic resistance). They were possibilities, not certainties, and not extreme. Possibilities are more certain than certainties, so with no strong reason to negate, the "all correct" answer fit. The deeper insight: UPSC usually does not invent false statements, so positive statements are often correct and negative qualifiers ("cannot") deserve special attention.
• Q37 (probiotics): Here there was no "all of the above", so at least one statement had to be wrong; the task was to find the odd one out. Statement 2 used the "this but not this" construction (found in foods we ingest but not naturally in the gut), a form UPSC frequently makes incorrect. Statement 3 was a non-extreme positive statement (probiotics help digest milk sugar). Eliminating the "but" statement led to the correct option.
• Q39 (vaccines): The simplest, most well-known fact was the trap. Statement 1 claimed Serum Institute's Covishield used mRNA, which most aspirants know is false. Eliminate the obvious error and you arrive at the answer without needing to know the harder trivia about other vaccines.
• Q40 (solar storm/solar flare): A solar flare is electromagnetic radiation, so GPS failure, power-grid damage, short-wave radio interruption, disturbed orbits and intense auroras all make sense. The question hinged on the tsunami statement. Tsunamis arise from movement in plates and have no one-to-one link with solar flares; the examiner was trying to confuse "flare" with "fire". Backing both the logic and the basics gave the correct answer.

After eight of the first eight, Neil Sir notes that even with a couple of mistakes your net stays strong, and with recent cutoffs around or below 50, the more you attempt using basic knowledge and common sense, the better your chances.

Who should watch this

This is for serious UPSC Prelims aspirants who freeze on unseen, fact-heavy questions and want a repeatable method instead of endless trivia. It suits anyone who has covered the basics once and now wants to convert partial knowledge into marks through reasoning, especially those preparing in the final months before Prelims.

The big message is that Prelims is built on revised basic sources plus common sense, and what cannot be solved from a source can be solved with logical reasoning learned by analysing past papers yourself. Try these heuristics under timed conditions on the Prelims test series, then return to the analysis on more UPSC guides to keep sharpening your question-attempt strategy.