Read the following information carefully and answer the question given below…

Concept: A relative's family term depends on two things together: the generation gap and whether the link is by blood or by marriage. A spouse's sibling is that spouse's brother-in-law or sister-in-law; a sibling's child is a nephew or niece; a daughter's husband is a son-in-law. Two people can share the same generation and still take a completely different label once a marriage tie is added in.

Application: A and B are the married couple, with A stated as the male member, so A is B's husband. C is described only as "the brother of A" — a same-generation sibling link to A. Applying the rule above, the brother of a woman's husband is that woman's brother-in-law. Since C is A's brother and A is B's husband, C is therefore the brother-in-law of B.

Cross-check: The rest of the stem is consistent with this reading. B is the daughter-in-law of F, whose husband has died, which makes F the mother of A (and so also the mother of C). D being C's only son and E being D's sister (so C's daughter) only extend the family tree — neither changes how C relates to B, so the brother-in-law reading holds without contradiction.

Why the other options don't fit:

• Brother — this names C's relationship to A, his own sibling; it does not by itself carry across the marriage tie to state how C relates to A's wife.

• Nephew — this label belongs to a sibling's son, one generation below C's actual level; C is A's own brother, not a child of any sibling in this family tree.

• Son-in-Law — this label belongs to the husband of one's daughter, one generation below B; C is a peer-generation brother of B's husband, not married to any child of B's.