---- How did you deal with the order? ---- I handed it to I think is in charge of sales.A

问题补充：

---- How did you deal with the order?

---- I handed it to I think is in charge of sales.

A. who

B. when

C. whoever

D. whomever

答案：

A. who

B. when

(答案→)C. whoever

D. whomever

解析：考查名词性从句。hand sth. to sb.“把某物交给某人”。to后是宾语从句，从句缺少主语，whoever“无论是谁”，不特指某个人。故选C。