A、will not be realized in the near future B、is still at a trial period C、is but a dream D、has been widely practiced B

Jackie: Andrew, How’s your toothache?
Andrew: It’s gone, thanks, Jackie. I went to the dentist last night and he took care of it.
Jackie: Which tooth was it?
Andrew: The last one on the upper right-hand side. It has a huge filling in it now.
Jackie: I hate having my teeth filled. It’s not just the pain I hate. I hate the sound of drilling.
Andrew: So do I. I’d rather have a tooth pulled than filled.
Jackie: Have you ever had one of your teeth pulled?
Andrew: No, but the one the dentist just fried will have to come out someday. He says it can’t be filled again.
Jackie: Teeth keep causing trouble, and nobody really does anything about it. I can’t understand why.
Andrew: They can put men on the moon, but they can’t keep people from having trouble with teeth.
Jackie: Why can’t they transplant teeth the way they transplant hearts? They can give somebody a different heart. Why can’t they give him different teeth?
Andrew: I’ve heard they’re working on that. My dentist says they’re working on tooth transplants right now.
Jackie: On second thought, I’m not sure I’d want to eat with some other person’s teeth.
Andrew: Well. That’s not how it works. The idea is to develop a plastic tooth that can be put into the hole where your own tooth came out.
Jackie: Really? What makes it stay there?
Andrew: So far they haven’t tried it with people, but they’ve made it work with baboons.
Jackie: Do they hook the plastic tooth to the teeth beside it?
Andrew: No, The plastic tooth is made with plastic roots, and after a while the gums grow around the roots, so the tooth can’t fall out.
Jackie: Are you making this up?
Andrew: No! Seriously, somebody at the Georgetown University Hospital in Washington has been working on it.
Jackie: Well, it sounds like a good idea.