Mobile computers-which (71) laptops, notebooks, subnotebooks and handhelds- (72) so ubiquitous in such a short time, no surprise to hear who say: "It will define the leading edge (73) the next five years or so." The most remarkable (74) mobile computers is the amount of data storage and memory packed (75) their tiny boxes. These devices not only handle windows easily but also run storage-hungry programs.

（71）处是（）

A.included
B.include
C.have included
D.have become
E.had become