Passage Four Questions 36 to 40 are based on the following passage. A computer virus is a piece of software programmed to perform one major task: to replicate. Viruses accomplish their reproductive task by preying on other computer files, requiring a host program as a means of survival. Viruses gain control over their host in various ways, for example,by attaching their infected code to the end of a host program and misguiding the header information at the beginning of the file so that it points toward itself rather than the legitimate program. Therefore, when an infected host program is run, the virus gets executed before the host. The host program can be almost anything: an application, part of the operating system, part of the system boot code, or a device driver. The virus continues to spread, moving from file to file in this infectious manner. In addition to its propagation mission, many viruses contain code whose purpose is to cause damage. In some viruses, this code is activated by a trigger mechanism. A trigger condition may be linked to the number of times the host file is run, or it could be a response to a particular date, time or random number.(S5)In other cases, the damage could occur continuously on a random basis. Of the 11,000 known viruses present today, more than 2000 have been diagnosed as being data destructive. All personal computers are at risk for viral infection. Several events, trends and technological in-roads have combined in the past few years to increase our vulnerability to infection. The proliferation of local area networks, the downloading of information from mainframes to desktop computers, our increased reliance on personal computers to store mission critical data, the arrival of electronic bulletin boards, the globalization of communications, the gained popularity of shareware, the growing use of remote communications, the portability of data, the casual spread of software via piracy, and the staggering rate of new virus creation all contribute to increase our risk of virus infection. 36. Which of the following is true according to the passage? A) Viruses gain control over their host through replacing the host files with their own. B) When an infected program is run, the virus gets executed together with the host. C) Viruses attack computer system by causing power failure. D) To replicate, viruses need a host system as a means of survival.
37. All of the following can be the host program except____. A) a device driver B) part of the system boot data C) part of the operating system D) a software
38. The trigger mechanism of damage can get executed____. A) at a particular time B) continuously C) on a random basis D) all of the above
39. Which of the following might not increase the risk of virus infection? A) Downloading of information from mainframes to desktop computers. B) The arrival of electronic bulletin boards. C) The portability of data. D) Popularity of personal computers.
40. The phrase “preying on” in the last sentence in the first paragraph means____. A) reproducing B) begging C) destroying D) inducing