Task: Dialogue Generation
Input (English): F: Here's your cup of coffee, Bob. ,M: Thanks. But what took you so long, Catherine? ,F: Sorry, Bob. I bumped into somebody I knew in the cafe and stopped for a chat.
(A) M: Oh, who's that you talked with? (B) M: Excuse me, could you repeat the question? (C) M: Oh, are you ok since you bumped into a coffee table? (D) M: It's ok, it didn't take you much time.
Output (English): A