● Melissa and LoveLetter made use of the trust that exists between or colleagues.Imagine receiving an  __(71)__  from a friend who asks you to open it.This is what happens with Melissa and several other similar email  __(72)__ .Upon running， such worms usually proceed to send other similar email addresses from the victim’ address book，previous emails， web pages  __(73)__  .
  As administrators seek to block dangerous email attachments through the recognition of well-known  __(74)__ ，virus writers use other extensions to circumvent such protection. Executable(.exe) files are renamed to .bat and NaNd 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 disaplaying some cute animation，simultaneously runs commands in the background to steal you password and give the  __(75)__  access to your network.
 

（71）A．attachmet B．packet

C．datagram 

D．message
 

（72）A．virtual

B．virus  

C．worms

D．bacteria
 

（73）A．memory

B．caches

C．ports

D．registers
 

（74）A．names 

B．cookies

C．software 

D．extensions
 

（75）A．cracker

B．user 

C．customer 

D．client