Third-person omniscient narrators are likely to be reliable because they're impersonal and know everything about the story they don't care enough about the characters to lie none of the above both "a" and "b"

They're impersonal and know everything about the story

Explanation:

Third person means that they are effectively "outside" the story, and that they are not directly affected or affecting anything in the story.

"Omniscient" means to "know all", and so an Third-person omniscient means that they are not part of the story and that they know all of what is going on.

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themselves

an intensive pronoun is a pronoun that ends in self or selves, such as himself, herself, themselves, yourself, ourselves. since band members is a third person plural, the correct intensive pronoun would be themselves. if the band was talked about as a collective noun, itself would be the appropriate intensive pronoun. intensive pronouns are used to add emphasis to the noun it's modifying which is why it directly follows it.