A、A teacher and a student. B、Classmates. C、Father and daughter. D、Mother and son. B这个对话中并没有任何明示这二人的关系，主要通过二人的对话内容进行推测。根据第三句 The

M: Hi. I have some good news for you.
W: What is it?
M: The teacher suggested that we go on a trip this Saturday.
W: Oh, wonderful. Where shall we go?
M: How about going to the park?
W: I don’t think it’s a good place to go to. We can go there another time. We should go farther away this time.
M: Where do you think we should go then?
W: How about the reservoir in the suburbs?
M: I don’t think it’s a good idea. It’s not safe. Why not go to the mountain instead?
W: That sounds good. Let’s go to the mountains to the south of the city.
8. What’s the probable relationship between the two speakers?