Which aspect does the test ability focus on?

The focus of test ability is primarily on the adequacy of the test basis and system design. This aspect is critical because it ensures that the tests are based on a solid foundation that accurately reflects the requirements and specifications of the system being tested. A well-defined test basis includes all relevant documentation, such as requirements, design documents, and user stories, which helps testers determine what needs to be validated or verified.

Additionally, the system design directly influences the test cases that can be derived to ensure comprehensive coverage of the application's functionality. If the test basis is inadequate, even the best-designed tests may not effectively evaluate the system's performance or behavior, leading to missed defects or insufficient testing coverage.

The adequacy of the test basis and system design is essential for creating effective test cases that translate testing activities into meaningful results, making this the core focus of test ability within the broader context of software testing practices.