A、Colleagues. B、Boss and secretary. C、Schoolmates. D、Roommates. A题目询问说话人之间的关系，通过女士说的“你出去玩而我照常工作”并且“还要替你干一些工作”，可以看出他们是同事关系，即选项A正确

W: Hello. How was your vacation?
M: It was great. A whole week at the seaside, swimming in the sum I feel completely relaxed.
W: (6) How I envy you! Do you know what I was doing when you were enjoying your life?
M: (7) Working as usual.
W: Right. And I was also asked to do some of your work.
M: I’m sorry. They should have waited for me to come back.
W: Don’t worry. Go to your desk and you’ll find lots of e-mails waiting for you.
M: Oh, it’s terrible, so many!
W: Well, it’s really hard for you to make up for the lost time.
M: Yeah, I agree.