Which malware type typically monitors user activity for advertising?

Spyware is a type of malware specifically designed to monitor user activity, often without the user’s knowledge or consent. It collects information about the user, such as browsing habits, search queries, and personal data, which can then be utilized for targeted advertising or sold to third parties. This stealthy collection of data is a hallmark of spyware, making it distinct from other types of malware.

Ransomware, on the other hand, focuses on encrypting a user’s files and demanding payment for the decryption key, while worms are designed to replicate themselves to spread across networks, not specifically to monitor user activities. Grayware refers to software that falls into a gray area between malicious and benign behavior, often exhibiting unwanted behaviors like adware, but it is not as targeted as spyware that specifically tracks user behavior for advertising purposes. Thus, spyware is the correct answer, as its primary function aligns closely with monitoring user activity for advertising.