Task: Dialogue Generation
Input (English): M: The post office should be open today. They only close on Sundays. ,F: Oh, then. It's good that I didn't wait until tomorrow to send this letter.
(A) M: Oh, tomorrow is Sunday. (B) M: But, today is Saturday. (C) M: I’m sorry, I don’t understand. Could you say it again? (D) M: Today is Monday. They should open now.
Output (English): B