A is the brother of B. C is the sister of A. D is the mother of B. How is D related to C?

B. MOTHER

If X - Y means X is the brother of Y, X + Z means X is the sister of Z, and Y × Z means Y is the father of Z, what is the relationship of X to Z in X - Y + Z?

B. X IS THE SISTER OF Z

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

A. SON

If X - Y means X is the sister of Y, X + Y means X is the brother of Y, and X × Y means X is the uncle of Y, what is the relationship of Z if X - Z + Y?

A. Z IS THE SISTER OF Y

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

A. FATHER