Sally can't have written tome,or-----the letter by now.A.I'd

Sally can't have written tome,or_____the letter by now.A.I'd have got B.I'd get
这两个选项到底选什么啊,我选的B但是答案写的A
这个应该是错综时间条件句吧,后面有NOW 就应该是与现在相反啊