Melissa and LoveLetter made use of the l:rust that exists between friends or colleagues.Imagine receiving an (1)from a friend who asks you to open it.This is what happens with Melissa and several other similar email (2).Upon running, such worms usually proceed to send themselves out to email addresses from the victim's address book, previous emails, web pages (3). As administrators seek to block dangerous email attachments through the recognition of well-known (4),virus writers use other extensions to circumvent such protection.Executable (.exe) files are renamed to .bat and .cmd plus a whole list of other extensions and will still run and successfully infect target users. Frequently, hackers try to penetrate networks by sending an attachment that looks like a flash movie, which, while displaying some cute animation, simultaneously runs commands in the background to steal your passwords and give the (5)access to your network.
空白（1）处应选择（）
A.attachment
B.packet
C.datagram
D.message
参考答案：A
解析：
Melissa和LoveLetter两种病毒主要是利用了朋友和同事之间的信任。想象你收到一个朋友寄来的电子邮件附件让你打开的情况。这就是Melissa和其他一些计算机网络蠕虫危害的方式。一旦运行，这些蠕虫通常会从受害者地址簿中、以前的邮件中和Web页面缓存区等地方发现邮件地址，发送带有病毒的邮件。当网络管理员试图通过识别常见的扩展名的方式阻塞危险信件的附件时，病毒作者使用其他的扩展名来伪装以不被阻塞。可执行文件被改名为批处理文件或命令文件或加一大串其他的扩展名，并且成功传染给目标用户。通常，黑客试图通过传送一个看起来像flash电影的附件穿过网络，在播放一些可爱的小动画的同时在后台运行命令来窃取密码，给解密高手留下通往网络的通路。