Answer:
C.The noun or pronoun that comes just before it.
Explanation:
The term apposition is part of the terminology proper to grammar, more specifically it is one of the elements of the subject of a sentence. The apposition is a noun that aims to identify the noun or pronoun that is close to it.
For example, read the following sentence:
I was fine, until Luan, my ex boyfriend, phoned me again.
In that phrase, the expression "my ex boyfriend" is an apposition that is identifying what is the noun "Luan".
