Much more research is needed _______ scientist find a drug that can safely provide the same effect o

题目

Much more research is needed _______ scientist find a drug that can safely provide the same effect on man.
A.where B.that C.until D.before
为什么不选C

答案

Until 在它意思为:在.之前,直到..才 的时候,常用语否定句中
He did not set foot in England again until 2002.
直到2002年他才再次来到英国踢球