Which statement best describes regression testing?

Regression testing is fundamentally about ensuring that recent changes or updates to software, such as bug fixes or new features, have not adversely affected the existing functionality. The primary goal is to detect any new faults that may have been introduced during the modification of the software. By running regression tests after changes are implemented, testers can confirm that previously working features still perform as expected.

In contrast, the other options focus on different aspects of software testing. For instance, ensuring all features function as intended pertains to initial functional testing, whereas checking for compliance with industry standards involves validating that the software meets specified regulatory criteria. Testing new features for user acceptance is aimed at evaluating whether these features meet user expectations and requirements rather than addressing potential issues with existing functionalities.