听力原文：M: Good morning.
W: Good morning, sir.
M: I'd like to enquire about flights to Paris.
W: Yes, sir.
M: Could you tell me how often they go？
W: Let me see. The first one leaves at seven in the morning, and then there's one every hour till eight in the evening.
M: Sorry, what time does the last one leave？
W: At eight, sir.
M: Thank you.
W: Pleasure, sir.
(8)

A. Traveler and agent.
B. Manager and worker.
C. Shop assistant and customer.
D. Classmates.