SoBig. F was the more visible of the two recent waves of infection, because it propagated itself by e-mail, meaning that victims

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问题     SoBig. F was the more visible of the two recent waves of infection, because it propagated itself by e-mail, meaning that victims noticed what was going on. SoBig. F was so effective that it caused substantial disruption even to those protected by anti-virus software. That was because so many copies of the virus spread that many machines were overwhelmed by messages from their own anti-virus software. On top of that, one common counter-measure backfired, increasing traffic still furthers. Anti-virus software often bounces a warning back to the sender of an infected e-mail, saying that the e-mail in question cannot be delivered because it contains a virus. SoBig. F was able to spoof this system by "harvesting" e-mail addresses from the hard disks of infected computers. Some of these addresses were then sent infected e-mails that had been doctored to look as though they had come from other harvested addresses. The latter were thus sent warnings, even though their machines may not have been infected.
    Kevin Haley of Symantec, a firm that makes anti-virus software, thinks that one reason SoBig. F was so much more effective than other viruses that work this way is because it was better at searching hard-drives for addresses. Brian King, of CERT, an internet-security center at Carnegie-Mellon University in Pittsburgh, note that, unlike its precursors, SoBig. F was capable of "multi-threading": it could send multiple e-mails simultaneously, allowing it to dispatch thousands in minutes.
    Blaster worked by creating a "buffer overrun in the remote procedure call". In other word, that means it attacked a piece of software used by Microsoft’s Windows operating system to allow one computer to control another. It did so by causing that software to use too much memory.
    Most worms work by exploiting weaknesses in an operating system, but whoever wrote Blaster had a particularly refined sense of humor, since the website under attack was the one from which users could obtain a program to fix the very weakness in Windows that the worm itself was exploiting.
    One way to deal with a wicked worm like Blaster is to design a fairy godmother worm that goes around repairing vulnerable machines automatically. In the case of Blaster someone seems to have tried exactly that with a program called Welchi. However, according to Mr. Haley, Welchi has caused almost as many problems as Blaster itself, by overwhelming networks with "pings"—signals that checked for the presence of other computers.
    Though both of these programs fell short of the apparent objectives of their authors, they still caused damage. For instance, they forced the shutdown of a number of computer networks, including the one used by the New York Times newsroom, and the one organizing trains operated by CSX, a freight company on America’s east coast. Computer scientists expect that it is only a matter of time before a truly devastating virus is unleashed.

选项 A、sending them an overpowering number of messages.
B、harvesting the addresses stored in the computers.
C、infecting the computers with an invisible virus.
D、destroying the anti-virus software of the computers.

答案A

解析 事实细节题。本文首段第二、三句指出"巨无霸如此有效,它能给那些有防毒软件保护的电脑造成很大的破坏。这主要是因为大量的病毒被复制传播,许多电脑被自己的防毒软件发出的无数信息压瘫痪了"。由此可知巨无霸病毒主要是通过给计算机发送大量的信息来毁坏计算机程序。
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