Remove it.
It adds nothing meaningful to the answer. It's noise that contains zero information. The help page about behavior of course only mentions signatures and taglines, since that's just as common, but the rationale for removing those fragments is the same: any visitor (or even the OP) who finds such a post will not care about this piece of text. Quite the contrary, it just takes up space on the page and wastes time of others.
Still, try not to get into an edit war over it. If the poster insists on having that sentence in their answer, let them do that. Tell them that it's not encouraged. If they continue adding it to every post they're writing, it might be necessary for a moderator to send them a reminder not to do it.
And either way, if that person always hopes that they've answered a question, or hopes that helps, then that'd make me wonder whether the user really should've posted an answer in the first place, or is just guessing.
See also: Should 'Hi', 'thanks,' taglines, and salutations be removed from posts?Should 'Hi', 'thanks,' taglines, and salutations be removed from posts?
