C.They. The pronoun that is not singular.
They is the third-person plural personal pronoun.
For example: Ben and Jerry are tall. They are basketball players.
They - signifies Ben and Jerry - compound subjects.
Everyone, anyone, everybody are collective nouns that take the singular verb form because these nouns are treated as one.
This is an internal conflict. It is internal because the person in it is struggling whether to do what the person wants to do or what is expected of the person. External would be between people and not between multiple parts of a single person.
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D. It suggests something violent and more dangerous.
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