More and more，the operations of our businesses，governments，and financial institutions are controlled by information that exists only inside computer memories．Anyone clever enough to modify this information for his own purposes can reap big reward．Even worse，a number of people who have done this and been caught at it have managed to get away without punishment．
It’s easy for computer crimes to go undetected if no one checks up on what the computer is doing．
But even if the crime is detected，the criminal may walk away not only unpunished but with a glowing recommendation from his former employers．
Of course，we have no statistics on crimes that go undetected．But it's disturbing to note how many of the crimes we do know about were detected by accident，not by systematic inspections or other security procedures．The computer criminals who have been caught may have been the victims of uncommonly bad luck．
Unlike other lawbreakers，who must leave the country，commit suicide，or go to jail，computer criminals sometimes escape punishment，demanding not only that they not be charged but that they be given good recommendations and perhaps other benefits．All too often，their demands have been met．
WhyBecause company executives are afraid of the bad publicity that would result if the public found out that their computer had been misused．They hesitate at the thought of a criminal boasting in open court of how he juggled the most confidential records right under the noses of the company’s executives，accountants，and security staff．And so another computer criminal departs with just the recommendations he needs to continue his crimes elsewhere．
The passage is mainly about_______．
A.why computer criminals are often able to escape punishment
B.why computer crimes are difficult to detect by systematic inspections
C.how computer criminals manage to get good recommendations from their former employers
D.why computer crimes can’t be eliminated