has finished the work ahead of time will be rewarded though we don’t know who it will be.

问题补充：

has finished the work ahead of time will be rewarded though we don’t know who it will be.

A. Those who

B. Anyone

C. Whoever

D. No matter who 

答案：

A. Those who

B. Anyone

(答案→)C. Whoever

D. No matter who 

解析：本题考查定语从句中的主谓一致问题。若选A的话,那先行词就是those,who指代those且在从句中作主语,那么从句的谓语应该是复数形式。若选B则在句中会出现两个谓语。D项只能引导让步状语从句,而不能引导主语从句。