Which of these choices are an example of a common?
1) a dairy cow
2) a service animal
3) a wild duck
4) a pet cat

4) A pet cat

Explanation:

Common can be define as the similarities in things, living beings, behavior, forms, shapes and others.

A pet cat is a domestic animal which can be found in many houses. Hence, it can be considered as common among human beings. A dairy cow cannot be kept by all although it is also a domestic animal. A service animal is also not found commonly everywhere. A wild duck can be found were a pond or river exists and it is also not common for all as it not kept as domestic pet.

A pet cat

Explanation:

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