A、The salesman. B、The man. C、Herself. D、A tutor. B判断题。从本文最后一句对话的回答中“You are”可判断出You即指the man，而不是指The salesman或tutor。所以A)、D)选项不对。

M: You look happy. Did you sell lots of things at the store today?
W: No. I bought something. It was a great deal.
M: So what is it?
W: A laptop computer.
M: Really? That’s great. It’s really convenient. You can take it anywhere.
W: That’s what I thought. I can use the computer at home and at my store.
M: What will you use it for at the store?
W: To keep track of all the things in the store, and how much I sell them for.
M: That’s a good idea. But I didn’t think you knew how to use a computer.
W: I don’t.
M: Then why did you buy one?
W: I’ve heard so much about computers. And I’ve heard you can find so many interesting things on-line. I was walking past the computer store downtown. I saw they had computers on sale.
M: So you went into the store to ask a few questions.
W: That’s fight. And I met a nice, young salesman. He showed me lots of things a computer can do. I just had to buy one.
M: So flow who’s going to teach you to use it?
W: You are.