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?
- (a) Q is a sister of S
- (b) Q is a daughter of S
- (c) Q is the mother of S
- (d) Q is a sister of the husband of S ✓ UPSC's answer
Why the answer is (d)
• S is the mother of T, so S is a woman; S is R's spouse, so R is a man.
• P has one son and one daughter, and Q and R are P's children. R is the son, so Q is the daughter.
• Q is the sister of R, who is S's husband: (d).
Why the other options are wrong
- (a) Q is a sister of S
- Q is S's sister-in-law, not her sister.
- (b) Q is a daughter of S
- S's child is T, not Q.
- (c) Q is the mother of S
- Q and S belong to the same generation.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2026, held on 24 May 2026. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.