以下有关计算机说法正确的是（）。

A.CPU的功能是负责计算机各种运算和控制整个计算机的工作

B.GHOST软件要求源设备的容量大于目标设备的容量

C.我们只能用FDISK进行分区

D.一个硬盘可以有四个主分区当一个主分区为活动分区其它被隐藏

Can you think        ?

A．what is his job

B．what does his job

C．what his job does

D．what his job is