On the farm, Curley's wife has basically no one to confide in. Her husband doesn't really love her and just uses her as a status symbol, while the rest of the farm are disinterested in her. Lennie doesn't really understand what she is talking about, but he is still a person, and she tells him all of the things that she really wants to talk about. Therefore, I believe the correct answer is choice D. Hope this helps!
