A、Preparing a presentation. B、Going for a car race. C、Doing housework. D、Doing her homework. D由原文可知，女士今天在忙着做家庭作业。因此答案为D。

M: Hi, Daphne, what are you busy with today?
W: Just some assignments after class.
M: I’m going for a car race. Would you join me? Come on!
W: Oh, Roger, do you really find car races fun to go to? It’s incredibly boring just watching the cars go around and around the track, and I can hardly breathe because of all the smoke and fumes!
M: You aren’t having fun? Daphne, car racing is the most popular sport in America.
W: I hate cars. They make so much pollution, which is creating holes in the ozone layer (臭氧层). And the environmental problems are only getting worse with global warming!
M: Daphne, cars are a part of American culture. Americans have always relied on cars instead of making do with public transportation.
W: Sorry, but what do you mean with "making do with public transportation"?
M: Oh, when you "make do" with something, that means you accept it reluctantly (不情愿地).
W: OK, I see. But, Roger, it’s often difficult to see how your lifestyle impacts the world. But we need to prevent pollution by driving cars less and investing in renewable energy.
M: Why do you like the environment so much? It’s full of mosquitoes that want to bite you, and bears that want to eat you!
W: If you’re not nice to nature, nature won’t be nice to you. If the polar ice caps (极地冰盖) melt, ocean levels will rise and flood the coastal cities.
M: Oh, Daphne, that isn’t going to happen. You watch too many movies.
W: Roger, most scientists agree that global warming is real, and there is evidence to show that the polar ice caps have been melting.
M: Well, what do you want me to do about it? I’m just one person. What can I do to make a difference?
W: Well, to start, you could buy more energy-efficient appliances. You could also think about buying an electric or hybrid car.
M: But I don’t have enough money for that!
W: But all of us are responsible for the environment, aren’t we?
M: Alright, Daphne. You’ve convinced me. I need to do more for the environment. I’m going to stop washing my clothes in the laundry machine to save electricity, and stop taking showers to save water.
W: What? Roger, there’s no need to go crazy, you know.
M: But Daphne, I have to do my part to save the environment! I’m going to "recycle" my dirty socks and wear them over and over again.
W: Roger, in that case the disgusting gases given off by your body are going to make a bigger hole in the ozone layer than all the cars in the world combined!
6. What is the woman busy with today?
7. What can we learn about car racing according to the man?
8. Which of the following environmental problems is NOT mentioned in the conversation?
9. What does the man say about Americans’ lifestyles?
10. How does the man think about the electric car?