PREP 124

124. 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

这题选E，可不可以这样理解：ensure与must重复呢？谢谢！

我觉得这题是would的问题，C,D时态错

A缺少thatB缺少would

1，ensure/must 重复

2，第二个that必须

   并于从句有两套主谓，分别用that引导。