听力原文：M1: Hello.
M2: Tom, this is Steve.
M1: Steve, wow. It's great to hear from you. How are you doing, cousin？
M2: Great, and I promise I'll make this quick, because I know you're probably beading out to the hospital, right？
M1: Hey, I've got all the time in the world. Ten minutes. Besides, I'm waiting for my frozen dinner to cook, so tell me, what's up？
M2: Well, dad tells me you two had a long talk on the subject of my future.
M1: Right, and you are thinking about becoming a doctor, aren't you？ I didn't know you had such good sense.
M2: Tom, I don't know where dad got this "surgeon" idea. Because I haven't really decided what I want to do... what I want to be... you know？ I mean, I'm not really sure right now that I even want to be a doctor.
M1: Aha.
M2: I mean, I'm interested, but I'm interested in a lot of other things too.
M1: Like photography, for instance.
M2: Yeah, exactly. You know all about that？
M1: Sure I do. I don't think I can remember ever seeing you without a camera slung around your neck.
M2: It's getting worse. This year I'm taking practically all the pictures for the school yearbook. I've built my own dark room, and I'm up to my armpits in negatives.
M1: Terrific! And that just goes to prove what I was telling your dad. It's early yet to decide what you're going to do with your life. After all, you are only.., seventeen years old and I think when you enter the college, you may choose some courses like geography, biology and other courses like art, music... [fade out]
What's the relationship between Tom and Steve？

A. Uncle and nephew.
B. Cousins.
C. Brothers.
D. Close friends.