Those may leave the classroom now.
A. whohasfinished
B. whohavefinished
C. havefinished
D. whomhavefinished
网友回答
A. whohasfinished
(答案→)B. whohavefinished
C. havefinished
D. whomhavefinished
解析：句意：已经完成的那些人现在可以离开教室了。这里是定语从句，先行词是those，who在从句中作主语，不能省去，因为它代指的是复数，故选B。