听力原文：M: What's that book you just picked up？W: The sociology text Professor Smith uses

听力原文：M: What's that book you just picked up？

W: The sociology text Professor Smith uses in his course.

M: You had better read it if you want to pass the course. Smith swears by it.

W: But it costs 40 dollars. I simply can't afford it.

M: Did you check the used book section here？ Maybe they have it.

W: No, they don't. I asked.

M: Why don't you get it from the library？

W: Are you joking？ I've been trying for months and it's always out. There are more than 45 students in the course and every single one wants the book.

M: Listen, you know my roommate, Henry, don't you？ He took the same course last year and I believe he owns the book. I'll ask him if he'll lend it to you.

W: Oh, Tom, that would solve everything.

Why doesn't the woman buy the book？

A．Because it's too expensive to buy it.

B．Because she doesn't need it.

C．Because she can't buy it everywhere.

D．Because she has already got one.