Some researchers believe that there is no doubt ______ a cure for AIDS will be found.

  A. which     B. that         C. what          D. whether 

B


解析:

主要測(cè)試同位語從句。結(jié)合平時(shí)的學(xué)習(xí)可知單詞doubt后面的引導(dǎo)詞：肯定句中用

whether或if；否定句中用that。因此答案已經(jīng)明了。意思：一些研究人員相信治療艾滋病的方法一定會(huì)找到的。例如：I have no doubt that he will come。我相信他會(huì)來的。

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