It is D, sharing appreciation for what is being said. Both A and B aren't crucial to being a good listener, in fact in practice they effectively draw attention to yourself, which would be fine if the question was regarding being a good conversationalist. Additionally, C is just completely irrelevant, that wouldn't even be a good conversation practice, let alone a trait important to listening.
I would say the best option would be C. because it’s the most likely option. Realistically speaking, it’s much more likely for a teenage mother to receive the opposite effects mentioned in the other options.
