Four friends - A, B, C, and D - have different pets: a dog, a cat, a bird, and a fish. A does not have a dog. B has a cat. C does not have a fish. Who has the dog?
In a family of five members - P, Q, R, S, and T - there are two males and three females. P is a teacher, Q is a doctor, and R is a male. S is not a teacher. Who is the doctor?