Given the task definition and input, reply with output. 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.

F: Hi, Mark! Have you finished the math yet? ,M: Yeah, it was really difficult. ,F: Well, I've got 2 free tickets for the Muse Concert. I wonder if you want to go this Saturday. ,M: Oh yeah! What time does it start? ,F: It starts at 8:00 so I'll call for you around 7:00. ,M: Could we make it a little later? I'll go to a basketball match at 3:00 and I won't be back till just before 7:00. ,F: OK. Well, 7:15, but no later. The traffic could be quite bad.
(A) M: I am sorry. You spoke so rapidly that I did not catch the meaning of what you said. Could you repeat that? (B) M: Sure. Let's meet at 7:30. Where should we meet? (C) M: OK. I'll leave home at 7:15 and meet you at 8:00. (D) M: Sure. I will meet you at 7:15. I won't be late.
D