Question $1$ options:

$123456$

Spyware

$123456$

Backdoor

$123456$

Worm

$123456$

Trojan Horse

$123456$

Virus

$123456$

Rootkit

$1.$

A program that is promoted and described as performing a useful function but that actually includes a hidden, malicious part

$2.$

A program that embeds itself$$ in $($i$.$e$.$ infects$)$ another program

$3.$

A type of malware that attempts to hide detection by installing itself in the operating system or by modifying the operating system to disable typical detection mechanisms

$4.$

A hidden program that permits access to a computer system or network

$5.$

A program, usually associated with online commerce that attempts to capture personal data or preferences, display ads or redirect users to certain websites

$6.$

A program, usually associated with email systems that propagates itself.$$ Once it infects an email system it can access the email address book and send out copies of itself to the recipients