单选题
Pharming is a scamming practice in which malicious
code is installed on a personal computer or server, misdirecting users
to{{U}} {{U}} 71 {{/U}} {{/U}}Web sites without their knowledge
or consent. Pharming has been called "phishing without a lure."
In phishing, the perpetrator sends out legitimate-{{U}} {{U}}
72 {{/U}} {{/U}}E-mails, appearing to come from some of the Web's most
popular sites, in ah effort to obtain personal and financial information from
individual recipients. But in pharming, larger numbers of computer users can
be{{U}} {{U}} 73 {{/U}} {{/U}}because it is not necessary to
target individuals one by one and no conscious action is required on the part of
the victim. In one form of pharming attack, code sent in an E-mail modifies
local host files on a personal computer. The host files convert URLs into the
number strings that the computer uses to access Web sites. A computer with a
compromised host file will go to the fake Web site even if a user types in the
correct Internet address or clicks on an affected{{U}} {{U}} 74
{{/U}} {{/U}}entry. Some spyware removal programs can correct the corruption,
but it frequently recurs unless the user changes browsing{{U}} {{U}}
75 {{/U}} {{/U}}.