In a coded relation, if M + N means M is the daughter of N, M - N means M is the son of N, and M × N means M is the grandfather of N, what is the relationship of O if M + O - N?
If A × B means A is the father of B, A + B means A is the sister of B, and A - B means A is the brother of B, what is the relationship of C if A × C + B?