秦初在我国东北居住的少数民族统称为突厥。

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Melissa and LoveLetter made use of the trust that exists between friends or colleagues. Imagine receiving an (16) from a friend who asks you to open it. This is what happens with Melissa and several other similar email (17) . Upon running, such worms usually proceed to send themselves out to email addresses from the victim’s address book, previous emails, web pages (18) .

A. memory B. cachesC. ports D. registers

As administrators seek to block dangerous email attachments through the recognition of well-known (19) , 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 (20) access to your network.