If M - N means M is the sister of N, and N + O means N is the brother of O, what is the relationship between M and O?

B. COUSIN

If A is the brother of B, and B is the sister of C, how is A related to C?

A. BROTHER

A is the grandfather of B. B is the son of C. How is C related to A?

A. SON

If G is the son of H and H is the brother of I, what is G's relationship to I?

A. NEPHEW

K is the son of L. M is the daughter of L. N is the brother of K. How is M related to N?

A. SISTER