A man points to a photograph: “The lady in the photograph is my nephew’s maternal grandmother.” The man has exactly one sister (no other sisters). How is the lady related to the man’s sister?

Introduction / Context:
We must connect “nephew’s maternal grandmother” to the man’s immediate family. The detail “who has no other sister” means the man has exactly one sister, preventing ambiguity.

Given Data / Assumptions:

• “Nephew” is the son of the man’s sibling. With only one sister, the nephew is the sister’s son (unless the brother has children, but the problem steers us to the simplest chain via the sister).
• “Maternal grandmother” of the nephew is the mother of the nephew’s mother.
• The nephew’s mother is the man’s sister.

Concept / Approach:
If the nephew is the sister’s child, then the nephew’s maternal grandmother is the sister’s mother—i.e., the man’s mother. Thus the lady is mother to the man’s sister.

Step-by-Step Solution:
Nephew = sister’s son.Maternal grandmother of nephew = mother of the sister.Therefore the lady is the mother of the man’s sister.

Verification / Alternative check:
If the nephew were a brother’s son, the maternal grandmother would be the brother’s wife’s mother, but the “only sister” clause and typical MCQ convention prefer the direct sister chain.

Why Other Options Are Wrong:
They indicate different collateral or in-law relations not supported by the primary reading.

Common Pitfalls:
Confusing maternal vs paternal grandparents.

Final Answer:
Mother