单项选择题

More and more, the operations of our businesses, governments, and financial institutions are controlled by information that exists only inside computer memories. (1) clever enough to modify this information for his own purposes can (2) big rewards. Even worse, a number of people who have clone this and been caught (3) it have managed to get away without punishment.
It’s easy for computer crimes to go (4) if no one checks up on what the computer is doing. But even if the crime is detected, the criminal may walk (5) not only unpunished but with a (6) recommendation from his (7) employers.
Of course, we have no statistics on crimes that go undetected. But it’s (8) to note how many of the crimes we do know about were detected (9) , not by systematic inspections or other security (10) . The computer criminals who have been caught may be the victims of (11) bad luck.
(12) other lawbreakers, who must leave the country, (13) suicide, or go to jail, computer criminals sometimes (14) punishment, demanding not only that they not be charged but that they be given good recommendations and perhaps other benefits. All too (15) , their demands have been met.
Why. Because company executives are afraid of the bad publicity that would result if the public found out that their computer had been misused. They (16) at the thought of a criminal (17) in open court of how he juggled the most confidential (18) right under the noses of the company’s executives, accountants, and security (19) . And so another computer criminal (20) with just the recommendations he needs to continue his crimes elsewhere.

A.at
B.with
C.of
D.by