控制器的功能是( )。

A．指挥、协调计算机各部件工作

B．进行算术运算和逻辑运算

C．存储数据和程序

D．控制数据的输入和输出

If there ______ no water, there ______ no life on the earth.

A．is, would be.

B．was, was.

C．were, would be.

D．were, would have.