M: Do we have to get the concert tickets in advance? ,F: Certainly, tickets at the door are usually sold at a higher price.
(A) M: So, you mean tickets at the door are usually sold at a lower price and the tickets are sold in advance at half price? (B) M: So, you mean we don't have to get the concert tickets in advance but it's difficult to buy the tickets on the spot? (C) M: Excuse me, could you repeat the question? (D) M: OK, I see. It's better to buy the tickets beforehand and we have to get the baseball tickets in advance.
C