【正确答案】 B

【答案解析】[听力原文]
In this dialogue, Reese is telling Beth all about a course on body language that he went on.
Reese: I have just finished this course on body language.
Beth: Ah, yeah?
Reese: Yes. It was really interesting. I learned all sort of useful things.
Beth: Ok.
Reese: Yes, well, if someone touches their nose while they are talking, it"s a sign that they are lying.
Beth: Right.
Reese: And if they are biting their nails, they are nervous or worried about something.
Beth: Ah, ha.
Reese: And if they form their arms across the chest, it means they feel threatened and being defensive.
Beth: Right.
Reese: And if they are leaning forward, it means they are interested. And if they are leaning back in the chair, it means that they are feeling very relaxed and confident.
Beth: Er, and what does it mean if someone yawns just like I did?
Reese: Oh, they didn"t tell us about that.
Beth: Well, I"ll tell you. It means that someone is really really really bored.
Reese: Oh, right, I"ll make a note of that one.
Beth: Yes, please do.