（）system let you run more than one program at a time.

单项选择题The（）is the primary device for entering information into The computer.

A.disk
B.printer
C.keyboard
D.memory

单项选择题（）is the process of converting text，sound，photos and video to data that can be processed by computer.

A.Computerization
B.Networking
C.Digitization
D.Informatization