Five animals - a dog, a cat, a rabbit, a parrot, and a fish - are kept in a pet store. The dog is not the smallest, the cat is smaller than the rabbit, and the fish is the smallest. Which animal is the largest?

A. DOG

A set of animals includes a dog, a cat, a parrot, a goldfish, and a hamster. Which animal is not a mammal?

C. PARROT

In a family, there are a father, a mother, two sons, and a daughter. If the father is a teacher and the mother is a doctor, which of the following is true?

C. AT LEAST ONE SON IS NOT A TEACHER.

A, B, C, D, and E are five students. A is older than B but younger than C. D is younger than E. If C is older than E, who is the youngest?

C. D

There are four types of pets: Dogs, Cats, Birds, and Fish. If all Dogs are friendly, and some Cats are not friendly, which of the following is true?

D. SOME PETS ARE NOT FRIENDLY