UPSC Prelims 2026 · CSAT
Question 3: Data Interpretation
If x and y are integers, then is x even?
- Statement Ix^2 y^2 is even.
- Statement II1 + x^2 + y^2 is odd.
Each item in this section contains a question followed by two statements. Answer each item using the following instructions and mark your response on the Answer Sheet accordingly.
AnswerUPSC’s answer is (c).
Statement I says xy is even, so x or y is even; x could still be odd. Statement II says x² + y² is even, so x and y have the same parity; both could be odd or both even. Together: if both were odd, xy would be odd, which contradicts I. So both are even, and x is even. Neither statement is enough alone, but the two together settle it.
Why each option is right or wrong
- (a) Wrong: neither statement alone works (I allows x odd with y even; II allows both odd).
- (b) Wrong: neither statement alone is sufficient.
- (c) Right: same parity from II plus an even product from I forces both even.
- (d) Wrong: the two statements together do give a definite answer.
Only the provisional key (27 May 2026) was found; the final key replaces it when found.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2026, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.