A)Joan may have taken a wrong train.
B)Joan will miss the next conference.
C)Joan won’t come to the conference.
D)Joan may be late for the opening speech.
原文：
M: Where is Joan? She said she would be here at three. And now it's three-thirty. She must have missed the train.
W: I think so, but I hope she won't miss the next one. Otherwise, she should be late for the opening address of the conference.
Q: What's the woman worried about?