问题
Perhaps John’s not in.—______.Look，the light’s on.
A:Yes，he can be at home
B:No，he couldn't go out
C:Yes，he must be at home
D:No，he needn't go out
B:No，he couldn't go out
C:Yes，he must be at home
D:No，he needn't go out
正确答案是：
