【单选题】

Speaker A: Listen. I've got some tickets for a great rock concert on Sunday night. Would you like to goSpeaker B: ______
A．Great! But I wonder if you have one more ticket so that I can bring my sister along.

B．All right. When will it start
C．Sunday Gee, I'd love to, but it's my mom's birthday.
D．Thanks ever so much.