单项选择题
M: I’d like to book a seat on the 8:30 flight to New York on 1 st July.
W: I’m sorry, sir. That flight is fully booked.
M: Oh, well, in that case I’ll go on the 10:30.
W: Yes, sir, we have seats on that flight.
A．The tickets were all sold out.
B．It has changed its take-off time.
C．The plane is too crowded.