Answer: C
Explanation: because I take AP Spanish and grammatically and I'm from Puerto Rico. On the sentence "Yo conozco a Eric" is talking about one person and the closest one is C.
It can't be A because "la" means or it's talking about a female
It can't be B because even though it's talking about a male, the "S" at the very end of the word is talking about more than one person.
It's not D because even though they have similar meaning, option C is coming from a third person point of view while option D is coming from a first person Point of view