题目内容：

英语反义疑问句选择题
1.The workers can't have finished their work yet,____?
a.have they b.do they C.are they D.can they
百度上搜索到一个：陈述部分为can't have done,依情况用did,has,have.
神马叫“依情况”= =汗
为什么选择A呢,D错在哪里~这边的have是使役动词吗?