What distinguishes black-box testing from white-box testing?

Black-box testing is fundamentally different from white-box testing in its approach to evaluating software applications. It focuses on assessing the software's functionality based solely on its specifications and requirements, without any consideration of the internal workings, architecture, or code structure of the application. This means that the testers conduct tests based on input and expected output derived from the application's functionality rather than understanding how that functionality is implemented.

When a tester employs black-box testing techniques, they are essentially verifying that the software meets the specified requirements and behaves as expected in various scenarios. This method allows testers to find discrepancies between actual and expected outcomes without needing to know the underlying logic or code, making it particularly useful for identifying issues related to user experience, performance, and logic from the end-user's perspective.

In contrast, white-box testing involves a thorough understanding of the internal code and logic, allowing testers to verify paths, branches, and conditions within the software. This approach requires detailed knowledge of the source code to evaluate the internal workings of the system.

Consequently, the correct response highlights the essence of black-box testing and its independence from code knowledge, marking it as a crucial method for ensuring that a product is functionally robust and aligned with user expectations.