In software engineering and systems engineering, ______ is a description of a system’s behavior as it responds to a request that originates from outside of that system.

As administrators seek to block dangerous email attachments through the recognition of well-known (9) , 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 passwouds and give the (10) access to your network.

A.hypertext
B.page
C.protocol
D.operation