May I speak to John?--This is ( )speaking.A.their B.his C.hi

C .him
其实可以说：This is John speaking.
或John speaking.
反身代词一般作宾语,且主语就是“他”本人.动作反作用到自己身上时用
如He taught himself English.
He hit himself.
还有是作同位语,表示“亲自”“本人”.如He himself did it.