【正确答案】
D
【答案解析】[听力原文] M: Morning, Myra. W: Oh hi, Arthur! You're taking Ecology 311, too? M: Looks like it It's my only elective course this term. W: Really? What happened? M: Oh, I just took too many my second year, and now I've got to pick up all the required courses I've been ignoring. University's just too much fun, I guess. And it has helped me decide my major, finally. W: What's it? M: I'm going for my BA in business administration. W: So, why 311? An ecology course isn't going to help you in your office job at some corporation. M: Probably not, but...it still seems interesting—and important. We all need to know about the environment, no matter what we do for a living. W: Yeah, you're right. And maybe you will be able to use it. Maybe you'll end up working for a green company or something. M: Could be. There's more and more of those every day. Is that why you're taking this? W: Well, it's not an elective for me. I need 311 for my BS program. We need several cross-field courses to 'broaden our understanding', and this is one of them. Actually, though, I'm looking forward to this course: 'Nature's Influence on Man—Man's Influence on Nature'! Sounds like a really useful topic, doesn't it? And Dr. Forsythe is supposed to be a very engaging lecturer. M: Yeah. Sure. W: Did you pick up your textbook yet? M: No. I've been looking for a secondhand copy before I spring for a new one. It's expensive—forty-five bucks! W: They all are, aren't they? Why do poor college students have to pay so much for their textbooks? It ain't fair. M: It's just economics. Nobody reads them except the students that take the courses. The publishers probably didn't print more than a few hundred copies of our text, you know. W: I suppose you're right. Where you gonna find a used copy? At the book-store? M: They don't have any there now—I checked. I put up some notes on the Science Building bulletin boards yesterday. Maybe someone there's got one they don't want to keep anymore. W: Well, uh, if you hear about two of them, will you let me know? I'd like to save a little money, too. M: Sure. If I do, I'll buy it for you and you can pay me back. How much are you willing to pay? W: Oh, anything under thirty-five dollars will be fine. A penny saved is a penny earned. But if you haven't found one by next Monday, I'll have to buy a new one then, so email me Sunday night either way, will you? M: You bet. Oops! It's almost 8:00. Here comes Dr. Forsythe. What is the possible relationship between the two speakers?