Which testing method focuses on assessing how easy it is for users to learn and operate software?

The correct choice emphasizes the importance of assessing the user experience, particularly how easily users can learn and operate a software application. Usability Testing is specifically designed to evaluate a product's interface and overall experience from the end user's perspective. This testing method involves observing real users as they interact with the application and gathering feedback on their experience, which includes factors such as ease of use, intuitiveness, and efficiency.

The core aim of Usability Testing is to identify any issues or barriers that users may encounter, which enables organizations to make informed improvements to the software. By focusing on real user interactions, this method ensures that the software aligns with users' expectations and needs, ultimately enhancing satisfaction and productivity.

In contrast, the other testing methods serve different purposes; for instance, Performance Testing assesses how the software behaves under various loads, Security Testing evaluates the software's vulnerability to threats, and Regression Testing focuses on ensuring that new code changes do not negatively affect existing functionality. Each of these areas plays a critical role in software quality assurance but does not specifically target the ease of learning and operating software as Usability Testing does.