(3)Computer experts have been gripped by fear of a dangerous illness.It is highly contagious,difficult to diagnose and in many cases impossible to cure.It is not computer experts or programming staff who are likely to be affected,but rather the elect

(3)Computer experts have been gripped by fear of a dangerous illness.It is highly contagious,difficult to diagnose and in many cases impossible to cure.It is not computer experts or programming staff who are likely to be affected,but rather the elect
(3)
Computer experts have been gripped by fear of a dangerous illness.It is highly contagious,difficult to diagnose and in many cases impossible to cure.
It is not computer experts or programming staff who are likely to be affected,but rather the electronic data banks themselves.Computer programmes are threatened by a computer “virus” that can paralyses entire computer networks once it has been smuggled into the system.
Initially,the viruses were quite harmless.Amateur computer enthusiasts smuggled them into big electronic systems,where they showed up as little massages or games.Such spectacular cases of computer espionage have shown that the big data banks are efficient,but also vulnerable.
Many experts complain that computer safety has been neglected for too long.By threatening to place a computer virus into the heart of the electronic data system,a large company could be put under extreme pressure.The damage done by computer viruses is already incalculable.The insidious thing about computer viruses is that if they are well programmed they will spread throughout the entire system unnoticed.Bit by bit they infect the programmes that they have access to and then one day they jump into action all at once.
And there seem to be hardly any counter measures.The chance of finding a computer virus in an electronic system without comprehensive know how and technical programme assistance is practically zero.
As an antidote,“virus blockers” have been introduced to keep viruses from entering and detect viruses tat have already gained access.The main attraction is that the virus blocker is the first anti virus programme that protects itself against virus infection.
1.According to this passage,computer viruses .
A.are not very harmful
B.can affect computer experts and programming staff
C.only attack the heart of the electronic data system
D.can make computer systems out of order
2.Computer viruses were first smuggled into computer systems by
A.computer experts?
B.programming staff?
C.amateur computer enthusiasts?
D.those who carry on espionage by computers
3.The infection of computer viruses is characterized by .
A.an insidious process
B.an immediate manifestation
C.an extreme pressure
D.a jumping action
4.To find a computer virus in an electronic system without comprehensive know how is .
A.very easy B.a good practice
C.almost impossible D.a technical problem
5.Which of the following statements is true?
A.Computer experts can do nothing to prevent computer viruses
B.Computer viruses have posed a great threat to computer systems
C.The damage done by computer viruses is not very great so far
D.The virus blocker can not protect itself against virus infection

(3)Computer experts have been gripped by fear of a dangerous illness.It is highly contagious,difficult to diagnose and in many cases impossible to cure.It is not computer experts or programming staff who are likely to be affected,but rather the elect
1.C
2.C
3.A
4.C
5.B