一道英语选择题 谢谢了呀

我也认为选C，句中的permitted by the law 作struggle的定语
句意是：他们应当采取这种为法律所允许的开放的斗争形式。
希望可以对你有所帮助~

They should take such open forms of stuggle______permitted by the law
A；that are B;as is C;which are D;as are

选C。