What task is primarily associated with adware?

Adware is primarily associated with displaying unwanted advertisements to users as they browse the internet. This type of software is often bundled with free applications and is designed to generate revenue through advertising. While some adware may track browsing habits to provide targeted ads, the main function remains the delivery of promotional content that users did not actively choose to view.

The other options address tasks that are not related to adware: improving security is a goal of antivirus and security software, encrypting files pertains to data protection and privacy measures, and updating software involves applying patches and improvements to existing applications. These tasks serve different purposes in the realm of software functionality and user interaction, clearly distinguishing them from the primary function of adware.