what is + somebody?意思是,“某人是做什么工作的?”所以这道题应该选A.What
who is + somebody?意思是,这个人是谁.要回答的是,他是你的什么人.如
who is this man?He is our teacher./He is my uncle/my neighbour.
what is this man?He is a teacher./He is a worker/a lawyer.
我想你一看例句就会明白.你好聪明。。。还好吧