听力原文：M: Pardon me, are you waiting in line for class registration？
W: Yes, I am. I think everybody in this line is as well.
M: I can't believe it! This line is huge. When I first walked up, I was hoping this wasn't for registration. How long have you been waiting？
W: About twenty minutes. It seems like the line goes pretty fast, but it's a long line.
M: I'll say!
W: I've watched a bunch of people who had been waiting in front of me leave. I guess they got disgusted and finally gave up. One couple said they had waited an hour and a half when they walked by.
M: Oh great! Do you have any idea why there are so many people？
W: I think the problem might be that the deadline as tomorrow. If you think it's had today, I bet tomorrow will be much worse.
M: I hope they don't close before we get to the front of the line.
W: I do too. I tried to use the automated telephone process to register, but it wasn't working right. That's probably another reason why the line is so long today. Last semester I registered for all of my classes over the phone.
M: Yeah, I've used that system before too, but I don't have a credit card anymore so I have to pay in person.
W: I don't know if that would have helped you very much. Apparently there were people who spent the night out here waiting to be first in line this morning.
M: That's really terrible. I can imagine somebody doing that for a concert, but just to register for classes it shouldn't be that difficult.
W: I know it, but I need to be in school this semester, so if that's what it takes, I'll do it.
(20)

A. They didn't have a credit card.
B. They couldn't want anymore.
C. They had spent the night in the line.
D. They felt ill.