Which of the following software monitors a user's activities and sends the information back to another source without the user knowing?

Malware

Explanation:

Some of the examples of Malware are Spyware, Viruses, Adware, Fake security software and Browser hijacking software. And these are a piece of codes, and if this is successfully installed on any computer, it spies through the user's activity, and without any consent of the users, sends all those personal and various other very sensitive data like credit card related information to the hacker. and who then take control of all your activities, and can threaten you, and ask for money to let you go free. Hence, always be clear to operate with only trusted parties.