听力原文：W: Professor Marnes, I wonder if you can fill me in on your lecture last Friday.I

听力原文：W: Professor Marnes, I wonder if you can fill me in on your lecture last Friday. I had to attend a scholarship award ceremony.

M: Oh well, congratulations. I hope you were rewarded handsomely!

W: Well, every bit helps. So, about your lecture, I understand you were talking about extinctions.

M: Yes. Well, the crux of my talk was just that we tend to think of extinction as a dramatic event, but most species die out over quite a period of time.

W: Why do they die off？ I thought they were continuously improving themselves. Natural selection, I think you once mentioned.

M: Ah, but you see while there is natural Competition between the species, what determines which species survive is largely by chance.

W: I don't get it. Why do species bother competing？

M: Well, there are short-term advantages. But many species also are helped by others. For example, the common housefly and cockroaches might have died off years ago if not for humans.

W: But you're not saying that humans are so successful merely because of chance？

M: To a certain extent, humans were initially lucky enough to have the right weather conditions and a lack of predators, but now, of course, we survive by ingenuity!

W: go we may never become extinct.

M: No, because we may be in a crash course to extinction by our continuous exploitation of the environment. We are a relatively young species and our time is hot yet overdue.

W: But there are 6 billion of us!

M: Yes and there're many more houseflies too! Each with the capacity to spread one disease from one person to another in a fast period of time.

(20)

A．She is writing a competitive paper for a scholarship.

B．She is doing a paper.

C．She missed the lecture.

D．She is planning to attend the scholarship award ceremony.