40. The boy has spent a whole day _____ in his room. No one knows what he is doing. A. locked B. t

40. The boy has spent a whole day _____ in his room. No one knows what he is doing. A. locked B. t
40. The boy has spent a whole day _____ in his room. No one knows what he is doing.
A. locked B. to loc k C. locking D. been locked