A pronoun can substitute a noun or a noun phrase. Among the options above only C. him and D. They are pronouns: stories is a noun and many could be a pronoun if is was standing alone, but here it is a part of a noun phrase.
C. him is singular, so the right answer is D. They
Imelda Marcos, First Lady of Phillipines (1965-1986)
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Imelda baby, what you do? XD