Answer:
Spyware
Explanation:
Spyware is a type of program that is installed with or without your permission on your personal computers to collect information about users, their computer or browsing habits tracks each and everything that you do without your knowledge and send it to remote user.
Security filter app that filters the accessibility of things it deems inappropriate
I'd have to say C. the steel as this is very physical as the others aren't as much which makes it stand out