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 filled 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’ ye 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.