补充题209

Television programs developed in conjunction with the marketing of toys, which was once prohibited by federal regulations, are thriving in the free market conditions permitted by the current Federal Communications Commission.

(A) Television programs developed in conjunction with the marketing of toys, which was once prohibited by federal regulations, are

(B) Television programs developed in conjunction with the marketing of toys, a practice that federal regulations once prohibited, is

(C) Developing television programs in conjunction with the marketing of toys, as once prohibited by federal regulations, is

(D) Federal regulations once prohibited developing television programs in conjunction with the marketing of toys, but they are（E）

(E) Federal regulations once prohibited developing television programs in conjunction with the marketing of toys, but such programs are

答案是E但我选了C.我觉得C的意思就是"Developing television programs in conjunction with the marketing of toys"这种practice "is thriving in the ..."这样理解哪里错了呢