A、The plane is delayed by the late arrival of some passengers. B、The plane is delayed by some mechanical failure. C、The weather

(Hu wants to get to his seat—a window seat.)
Hu: Excuse me, sorry to bother you!
Man: Not at all! (standing up to let Hu pass)
Hu: Thanks a lot! (squeezing past) These seats don’t get any roomier, do they!
Man: No, they don’t!
Hu: Thank you very much!
(A few minutes later...)
Captain: "This is your captain speaking! Welcome aboard the aircraft, ladies and gentlemen! I am sorry to say that there is a small problem, caused by the late arrival of passengers, and we shall be delayed for a short while before leaving. We’ll keep you informed of developments. Thank you !"
Hu: Oh, dear! That’s bad news!
Man: Yes, it is.
Hu: There’s no danger of our missing connecting flights at the other end, is them, do you think?
Man: Hard to say! We’ll probably be all fight.
Hu: I hope so!
Captain: "Hello again, ladies and gentlemen! This is your captain speaking! I’m sorry about the slight delay. You’ll be pleased to hear that everything’s been sorted out, and we’ll be taking off in the next few minutes. Thank you!"
Hu: That’s a relief.
Man: Yes, well, these things are usually sorted out in the end!
Hu: It sounds as though you are a regular on this flight.
Man: I do it two or three times a year perhaps.
Hu: Business rather than pleasure, I suppose!
Man: I’m afraid so! What about you?
Hu: Oh, I’m off on a study tour of biochemical firms in Australia.
Man: Oh, that’s interesting!
Hu: I hope so. Do you have anything to do with any of those companies?
Man: Not really, although, as a matter of fact, I did...