请英语高手们来看看这道虚拟句.
Mr.Green________my letter,otherwise he would have replied before now.
A,must have received B,must have failed to receive C,must receive D,must fail to receive
otherwise 的虚拟句一般不是其前的句子用一般陈述语气,后用虚拟语气吗?那应该选D啊,