I still haven't got the letter he sent to me a week ago.I wonder if the letter___ wrongly delivered[A] might be [B] might have been[C] should be [D] should have beenAnd reason,please.Thanks.

I still haven't got the letter he sent to me a week ago.I wonder if the letter___ wrongly delivered[A] might be [B] might have been[C] should be [D] should have beenAnd reason,please.Thanks.
I still haven't got the letter he sent to me a week ago.I wonder if the letter___ wrongly delivered
[A] might be [B] might have been
[C] should be [D] should have been
And reason,please.Thanks.

I still haven't got the letter he sent to me a week ago.I wonder if the letter___ wrongly delivered[A] might be [B] might have been[C] should be [D] should have beenAnd reason,please.Thanks.
A 我感觉might 是和否定句还有疑问句一起的
要嘛a要嘛b b是一直持续在做的事 这封信早已收到

B

B

选D，是过去将来完成时，should 换成would可能更好理解。