If A + B means A is the mother of B, and B - C means B is the sister of C, what is the relationship of A to C?

B. AUNT

P is the uncle of Q. R is the sister of P. How is R related to Q?

A. AUNT

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

A. SISTER

If P is the uncle of Q and Q is the daughter of R, what is R's relation to P?

C. SISTER-IN-LAW

If M is the grandmother of N and N is the son of O, what is O's relation to M?

D. CHILD