No letters ____from her since she went to work in Africahave been receivedhas been receivedreceivedare received哪个\?为什么

No letters ____from her since she went to work in Africahave been receivedhas been receivedreceivedare received哪个\?为什么
No letters ____from her since she went to work in Africa
have been received
has been received
received
are received
哪个\?为什么

No letters ____from her since she went to work in Africahave been receivedhas been receivedreceivedare received哪个\?为什么
我觉得是has been received
no letters谓语动词用单数