In this task you are given a small conversation between two persons and 4 options on how the conversation should continue. Your job is to choose the most reasonable option. The conversation and the options are separated by a newline character. Each dialogue in the conversation are separated by a comma. F and M indicate female and male, respectively.

Ex Input:
F: How long have you been living in this city, Jack? ,M: Let me see. I came to this city when I was 23 years old. So 5 years now. ,F: Do you like living in the big city? ,M: Not so much. Air pollution has become such a big problem here now.
(A) F: I agree with you. Heavy traffic is a serious problem. (B) F: I agree with you. Air pollution is not a serious problem. (C) F: I am afraid I did not quite catch what you were saying. Please repeat it. (D) F: I agree with you. Air pollution should be paid more attention to.

Ex Output:
D

Ex Input:
F: How much is this piano, please? ,M: $1000. ,F: My god! That's a fortune! ,M: But you must realize that this is the most famous brand. ,F: But it's too dear for me. ,M: That's the best piano hit our store. ,F: I just want to get one for my daughter to learn how to play the piano.
(A) M: If you want to buy yourself a piano, this one is perfect. It is a niche brand and is the best piano in our store. (B) M: I'm sorry, I didn't understand. Could you repeat a little louder, please? (C) M: This is the best piano we have and it costs only $1500. It should be the best choice for your son. (D) M: This piano will suit your daughter very well since it is the most famous brand. She must like it.

Ex Output:
D

Ex Input:
F: Excuse me, could you please tell me how I can get to the shopping center? ,M: You can take the bus number 11 in front of the Mattson Center. ,F: How often does it run? ,M: Every 30 minutes on weekends, every 15 minutes on weekdays.
(A) F: I'd like to go there by subway. (B) F: Just a minute! I do not quite follow what you are saying, would you mind repeating that? (C) F: OK. I'll go to that university by bus. (D) F: OK. I'll to the shopping center by bus.

Ex Output:
D