A man pointing to a photograph says–“The lady in the photograph is my nephew’s maternal grand-mother”. How is the lady in the photograph related to the man’s sister, who has no other sister? she is

Work from the nephew outwards. A maternal grandmother is the mother of the child's mother. So the lady is the mother of the nephew's mother. The man's sister is the nephew's mother here, since the man's nephew is the child of one of his siblings. That makes the lady the mother of the man's sister, which is option C.

The clue "who has no other sister" fixes the family. The lady is the sister's mother, and because the sister has no other sister, the lady cannot be read as the mother of some other sister.

• A) Cousin: A cousin shares a grandparent, not a parent. The lady is a parent of the sister, so she is one generation above.
• B) Sister-in-law: This needs the lady to be the wife of the sister's brother, or the sister of her spouse. Neither fits the given statement.
• D) Mother-in-law: This would require the sister to be married to the lady's son. Nothing in the statement says that, and the nephew's line points to a direct parent-child link.

Core concept: relationship chains built from one given statement, where you trace the link from the target person to the known person one generation at a time. This is the same logic used in Prelims blood-relation questions and in Mains answers on family and kinship structures.

Trap: Aspirants jump to "mother-in-law" because the question mentions marriage through the nephew. Check first whether the nephew's mother is the sister or the sister-in-law. In this question the sister is the nephew's mother, which makes the lady her direct mother.