题目内容：

My father asked him_____ Awhy to do B what he did it for C what to do it Dhow he did with it

优质解答

此题应选D
楼上选B,我有异议.因为若选B,what应该是充当did的宾语,而B项中did已有宾语it,　故did有两个宾语,一个是what,一个是it,二者重复.排除C的理由也是如此,do有两个宾语,重复.