A、Because his car was broken. B、Because no one gave him a ride and the bus was delayed. C、Because the bus he took was broken on

W: Jim, thank goodness, you’ve arrived! The class presentation started half an hour ago. And I was just beginning to panic!
M: I’m sorry I’m late, Ellen. This morning has been a real mess. I didn’t think I was able to make it here at all.
W: Why are you late? Our whole presentation depends on the graphs you’re holding.
M: Yes, I know. I’ll tell you about it later. First, let’s see how we’re doing for time.[14]Two groups are still ahead of us, I think—the presentation on the rights of the consumer and the analysis of the stock market. That means we’ve got about 30 minutes to warm up.
W: You do look cold! What happened?
M: I’ve been standing outside in arctic temperature for over an hour, waiting for a bus.
W: Over an hour? But I thought your apartment was only a 10-minute bus ride to campus under normal conditions.
M:[15]But the bus was delayed because of the weather. And when I stepped into a drug store to call home for a ride, the bus went by. As luck would have it, there was no one at home, so I had to wait another 45 minutes for the next bus.
W: That’s Murphy’s Law, isn’t it? What was it he said? If anything can go wrong, it will.[13]Well, we’ve still got 20 minutes to gather our wits together.
M: We’d better stop talking. People are turning around and looking at us.
12. What are they mainly talking about?
13. How much time is left for them to prepare for their presentation at last?
14. What do they probably major in?
15. Why was the man late for class?