At the end of the meeting ,it was announced that an agreement-------.Ahas been reached B had been r

At the end of the meeting ,it was announced that an agreement-------.Ahas been reached B had been r
At the end of the meeting ,it was announced that an agreement-------.Ahas been reached B had been r

At the end of the meeting ,it was announced that an agreement-------.Ahas been reached B had been r
B
主句为过去式,从句也要为过去式时态,所以选B

应该选择B
选择B的理由是因为在前句 It was announced that ...已经表示是过去式.所以肯定是决定了之後再发表的,也就是说决定在发表的之前,所以就用过去完成时..所以用had been reached...会比较make sense.

B