Professor Li always allows his students to voice their opinions in class sometimes their

问题补充：

Professor Li always allows his students to voice their opinions in class, sometimes their opinions are not sound.

A. so that

B. in case

C. even if

D. as though

答案：

A. so that

B. in case

(答案→)C. even if

D. as though

解析：

这题考查连词辨析：so that为了，in case以防，even if 既然，as though好像，根据句意：李教授经常让学生说出自己的观点，即使他们的观点不合理。选C。