2026 CSAT, all questions
UPSC Prelims 2026 · CSAT
Question 44: Logical Reasoning and Mental Ability
P has a son and a daughter. S is the mother of T. S is R’s spouse. Q and R are children of P. Then how is Q related to S?
aQ is a sister of S
bQ is a daughter of S
cQ is the mother of S
dQ is a sister of the husband of S
AnswerUPSC’s answer is (d).
Q and R are P's two children, one son and one daughter. S is R's spouse and the mother of T, so S is a woman and R is a man. R is therefore the son and Q is the daughter. Q is R's sister. Since R is S's husband, Q is the sister of S's husband.
Why each option is right or wrong
- (a) Wrong: Q is R's sister, not S's sister; S is R's wife.
- (b) Wrong: Q is P's daughter, not S's.
- (c) Wrong: Q is R's sister, so she cannot be S's mother.
- (d) Right: Q is the sister of R, who is S's husband.
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.