[求助]大全885 04-16请教大家

16.   One
of Ronald Reagan’s first acts as President was to rescind President Carter’s
directive that any chemical banned on medical grounds in the United States
be prohibited from sale to other countries. 
A

(A) that any
chemical banned on medical grounds in the United States be prohibited from sale
to other countries

(B) that any
chemical be prohibited from sale to other countries that was banned on medical
grounds in the United States

(C) prohibiting
the sale to other countries of any chemical banned on medical grounds in the
United States

(D) prohibiting
that any chemical banned on medical grounds in the United States is sold to
other countries（C）

(E) that any
chemical banned in the United States on medical grounds is prohibited from
being sold to other countries

这道题正解是C，我选的A，请问A和C有什么区别，仅仅是主动由于被动吗，还有D中有什么问题，是prohibit不能加从句吗，请指教