answer vs reply

Answer and reply are synonyms- there is a slight nuance in meaning, though (or simply in frequency of collocation and use):

• reply: you typically reply to something that has been said

• answer: you typically answer a question (you always say 'questions and answers', or 'an answer to a question'; you would never use reply in that context).

In this example:

A: Can you tell me how to get to the railway station?

B: I'm sorry, I've no idea, I don't live here.

I think B's response is a reply, but not an answer. An answer means A finds out where the station is.

For example you answer the phone, you don't respond or reply.