prep-1-141were的困惑~!~!~

141.       (32450-!-item-!-188;#058&006160)

The federal rules aimed at protecting human subjects of medical experiments were established to ensure that patients must be warned of potential risks and an independent panel would evaluate the experiment before it was conducted.

(A) must be warned of potential risks and an independent panel would

(B) must be warned of potential risks and that an independent panel

(C) are warned about potential risks and that an independent panel

(D) will be warned about potential risks and an independent panel would

(E) would be warned of potential risks and that an independent panel would

(B) must be和ensure有语意上的重复；ensure后的内容尽量与主句时态一致，过去发生的事情应该用would。

(C) are warned时态不正确，过去发生的事情应该用would. 为什么用would呢 若是过去形式 应该用were啊??

(D) will be时态不正确，与后面的would也不平行；and后面缺少宾语从句引导词that。

(E) 正确，emsure that… would and that … would…时态及形式都平行对称。

请各位NN指教~谢谢了!!!

明白!!!!

谢谢aeoluseros!!! (给你换个底色再!!)