We should try our best to keep our environment from.A. pollutingB. pollutedC. being pollut

问题补充：

We should try our best to keep our environment from.

A. polluting

B. polluted

C. being polluted

D. having polluted

答案：

A. polluting

B. polluted

(答案→)C. being polluted

D. having polluted

解析：考查固定搭配和动名词的被动形式；固定搭配:keep sth from doing sth阻止某人做某事；句意：我们应该努力阻止我们的环境被破坏。本句的环境和破坏之间构成被动关系，故使用动名词的被动形式being done。故C正确。