X is the mother of Y. Y has a brother Z. What is Z's relation to X?

A. SON

D is the mother of E and F. G is the brother of D. How is G related to E?

A. UNCLE

D is the father of E and F. G is the sister of E. How is G related to F?

A. SISTER

M is the uncle of N. N is the daughter of O. How is O related to M?

B. SISTER

X is the father of Y. Y is married to Z. Z has a brother W. How is W related to X?

C. BROTHER-IN-LAW