[听力原文]8-10
W: Welcome, Mr. Johnson. Take a seat, please. Our manager will be back soon.
M: Thank you. Urn, it’s rather warm these days, isn’t it
W: Yes. The weather is quite unusual at this time of year.
M: You’re right. Er...do you mind if I take off my jacket then
W: Sure. Make yourself at home.
M: Thank you, that’s better. Urn...do you mind if I smoke I notice nobody’s smoking around here.
W: Well, I’m sorry, but this is a non-smoking office building.
M: Oh, that’s OK. I’m trying to quit it anyway. By the way, may I use your phone to book a table... for lunch
W: Yeah. Sure. Do you know which restaurant is good
M: Oh, yeah, absolutely.
W: Fine. The phone is over there.
M: Thank you.

What’s the most probable relationship between the two speakers（）

A．Doctor and patient.
B．Manager and clerk.
C．Secretary and visitor.
D．Teacher and student.