Task: Dialogue Generation
Input (English): F: What's the matter? ,M: I've been having a lot of headaches recently.
(A) F: You have got so much pressure from work! But you never have a headache, right? (B) F: Just a minute! I do not quite follow what you are saying, would you mind repeating that? (C) F: Are you OK? How long do you usually lose sleep at night? (D) F: Are you OK? How long have you been having headaches?
Output (English): D