A、By filling in the hole. B、By repairing the tooth. C、By using a dentist’s drill. D、By using laughing gas. D选项均是表方式的介词By引导的短语，可见

W: Hi, Dr. Hyde.
M: So, what seems to be the problem today?
W: Well, I just came in for a check up and a dental cleaning.
M: Hum. Open up. Let’s take a look.
W: Ok. Uh...
M: Well, there is a major cavity in one of your wisdom teeth. Hasn’t this given you any trouble?
W: Well, the tooth has been bothering me, and it sometimes hurts when I try some grapefruit or an ice-cream. Is it really bad?
M: Well, we’re going to remove the decay, and then we’ll either put a filling in, or if the decay is extensive, we can’t repair it, we might have to put a crown on your tooth. Or as a last resort, we may have to extract the tooth.
W: Uh, well, that sounds painful!
M: Don’t worry. I’ve done this... once before. Nah, just relax.
W: Wait! Aren’t you supposed to give me something to dull the pain?
M: Uh, chicken. Oh yeah. I almost forgot. We can either use a local anesthetic or laughing gas to minimize the discomfort you might feel. Or you can just grin and bear it.
W: Nah, Nah, nah! I can’t stand pain, and I’d rather not be aware of what’s going on And, if I need a filling, can I get one that looks like my other teeth?
M: If we can save the tooth with a filling, I recommend a high-strength silver alloy filling instead of a porcelain one. It’ll probably last longer.
W: OK, well, whatever. Let’s get it over with.
M: Okay, pleasant dreams. Drill please.
5. What is the woman’s initial reason for visiting the dentist?
6. What problem does the dentist discover?
7. How can the discomfort the woman might feel be minimized?
8. What is the treatment the woman probably receive?