Although the bulk of industry resources and energies have focused on developing the fastest (71) or slickest (72) , more and more mindshare is turning to the evolution of the computer interface. Advancements in the areas of input devices, (73) processing and vitual reality could lead to fundamental changes in the way human and computer interact. The technological battlefield of the future will be adding layers between the user and the raw machine to make the (74) as invisible as possible. (75) crepresents the next evolutionary step for the interface.
A．explicit
B．voice
C．implicit
D．special