A、His inbox was broken. B、He made a big mistake. C、The meeting was put off. D、The work was postponed. C女士说会议推迟到星期五，男士说：什么?会议推迟了?

M: I have been waiting here in the conference room for ten minutes already. What time does our meeting start? Where is everyone anyway?
W: Didn’t you hear about that? Our meeting was postponed until Friday.
M:[19]What? The meeting was postponed? No one told me anything about it.
W: Didn’t you get the memo?
M: What memo? There haven’t been any memos this whole week. I check my inbox every day, and I haven’t seen anything.
W: The memo went out 3 days ago. It should have made it to your inbox, but maybe lost in all collectors on your desk.
M: You know how things get piled up on my desk when I am busy. I know that sometimes I do misplace things, but I always read all the memos that go around. They go directly to my inbox. Are you sure it was sent to the whole office?
W: It should have gone around to everybody. They also posted a copy of the memo in the break room. Don’t you ever look at the messages posted on the bulletin board?
M: I am usually too busy to take a bunch of coffee breaks. Anyway, I’m sure the memo never got to my inbox. I’ll have to talk to our secretary about it.
W: That’s right. You never know what you’re missing out of if you don’t read the memos.
19. What didn’t the man know?
20. What do we learn about the memo?
21. What will the man do after the conversation?