Modern computers are electronic and (8) devices. The basic building block of a modem computer is a (9) .
A) chemical B) digital C) phisical D) anal0g

A．24
B．32
C．36
D．40

A) 节省文件所占的存储空间
B) 减少实际输入、输出的文件次数
C) 实现进程间相互通信
D) 节约内存，减少存储空闲区