They are discussing in the next roomwill go to the conference on behalf of the manager.A.

问题补充：

They are discussing in the next roomwill go to the conference on behalf of the manager.

A. whoever

B. who

C. what

D. whomever

答案：

A. whoever

(答案→)B. who

C. what

D. whomever

解析：考查名词性从句。who引导宾语从句，这里不需要用强调形式whoever。