There is no question that computer applications such as (71) , electronic mail, and (72) publishing have changed the way people work. These computer applications have enhanced users capacity for communication and have improved their productivity. The success of these applications has prompted both vendors and researchers to continue to seek new ways to further advance the information technology revolution. Enter the latest innovation: networked (73) systems. They convey information in multiple (74) : text, graphics, video, audio, (75) , computer simulations, and so forth. Advocates of these systems argue that they are the next logical step in human communication; however, modifying our current networks to accommodate the variety of media will present significant technical difficulties.

A．kinds

B．classes

C．formats

D．varieties

积屑瘤在加工中没有好处，应设法避免。