在电子商务活动中，如果一个黑客修改了在因特网上传输的订单信息，那么这是对数据的( )的破坏。
A. 完整性
B. 可用性
C. 有效性
D. 高效性
Directed research may become a danger to the future of science because______.
A. pure research may be neglected under this system
B. the division between the pure and the applied scientist will disappear
C. the interdependence of pure and applied science may be ignored
D. both A and C
The word "assert" (line 4, paragraph 3) might mean______.
A. refute
B. declare
C. deny
D. cite
A Spear or a robot has the quality of technology only when it______.
A. is used both as a cultural and a physical object
B. serves different purposes equally well
C. is utilized by man
D. can be of use to both man and animal
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