If A + B means A is the brother of B, A - B means A is the sister of B, and A × B means A is the father of B, what is the relationship of C if A + B × C?
There are four animals: a dog, a cat, a parrot, and a goldfish. The dog and cat are mammals, the parrot is a bird, and the goldfish is a fish. Which animal does not belong to the same category as the others?