A、Booking a theatre ticket. B、Reserving a room. C、Booking an air ticket. D、Reserving a seat. C问题问的是对话讨论的主题是什么。根据男士所说Will you boo

M：Good morning.Will you book a plane ticket to London for me?
W：Yes, sir.What time would you like to leave?
M：The 21st of December.
W：There are several flights available.
M：Morning flights will be perfect.
W：Yes，sir.There is a flight available on that day, at 10：00 am.
M：Fine.I’ll take that flight, then.
Q15：What does the conversation talk about?
Q16：What’s the relationship between the two speakers?