F: I have no idea whether they will come or not. ,M: There is no need to worry about it. We have enough seats for them.
(A) F: You're right. But I'm still not sure of the amount of seats. (B) F: All right. I will not worry about whether my friends will come or not. (C) F: I’m sorry, I don’t understand. Could you say it again? (D) F: I'm so glad that you like my idea. Let's be ready to invite my parents.
B