Three fourths of the homework ______ today.

A.has finished

B.has been finished

C.have finished

D.have been finished

答案及解析： B

解析：

考查时态及主谓一致。句意：今天有四分之一的作业被完成了。可知本句描述的是现在已完成的动作。当前面有分数修饰时，谓语动词与被修饰词保持一直，homework为抽象名词不可数，故谓语动词用单数，选B。