Without facts we can’t form a correct opinion for we need to have actual knowledge our t

问题补充：

Without facts, we can’t form a correct opinion, for we need to have actual knowledge our thinking.

A. which to be based on

B. which to base on

C. on which to base

D. which to base

答案：

A. which to be based on

B. which to base on

(答案→)C. on which to base

D. which to base

解析：base our thinking on actual knowledge “将我们的思维建立在实际的知识基础之上” , 此处为不定式短语作定语,修饰knowledge .