A、$100. B、$200. C、$300. D、$ 350. C对话中，男士提到the Power Macintosh G3正在做活动，学生打七折，故本题答案为C。

M: Can I help you?
W: Yes, I need to buy a computer for this semester. I was told it is cheaper to buy computers here.
M: Well, you heard right. We have great discounts for students.
W: I don’t know much about computer, and (19)I want a desktop computer with large memory.
M: Well, (20)I highly recommend the Power Macintosh G3. It comes with 64 megabytes of total memory. It should be enough for any student needs you might have. We have a special deal on right now. I should tell you about it, as it only goes until next Tuesday. (20)If you want one, you can actually get 30 percent off the usual sale price.
W: Wow. That’s really good. Hey, wait. Is this an Apple computer?
M: Yes, it’s a Macintosh. It’s Apple. Macintosh and Apple are the same thing.
W: (21)I don’t want Macintosh, as nobody in the university uses Macintosh. I want PC.
M: Well, most of the students and professors in the university here use Macintosh. May I ask where you’re from?
W: I’m from China.
M: Well, I know that in most Asian countries Apple is not very popular. But here in America, especially in universities and publishing companies, Apple is very commonly used.
W: But I need a computer that can handle writing in Chinese.
M: There are several Chinese writing programs you can use with Macintosh. Chinese is no problem for Apple.
W: Hmm. I think I should ask some of my friends for advice before I make a decision. I’m sorry.
M: No, don’t be sorry. It’s reasonable to ask your friends. Here is my card, if you need any help.