X and Y are brothers. M is Y's wife. N is X's son. How is N related to M?
Correct: A
X and Y are brothers. M is married to Y, making her Y's wife and X's sister-in-law. N is the son of X. Since N is the son of Y's brother (X), he is Y's nephew. As M is Y's wife, she is also N's aunt via Y. Thus, N is M's nephew.