W: Hi, Robert, what happened to your face? It looks swollen. M: I have to go and get my teeth filled. W: Did it hurt? M: I don't even want to talk about it. It killed me! W: Well, I guess you've learned a good lesson, huh! You have to take good care of your teeth. M: No kidding. I can't stand the pain, but the bill is too large! W: Don't you have a dental insurance? M: I do. but it doesn't cover everything., Question: What is the topic of the dialogue? (A) Headache. (B) Toothache. (C) Insurance.
(B) Toothache.