单选题 Speaker A: Listen. I've got some tickets for a great rock concert on Sunday night. Would you like to go?
Speaker 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.