Certified Associate in Software Testing (CAST) Practice Test

Testability measures the:

1. Extent to which a program can be repurposed

2. Preparation needed for software transfer between systems

3. Effort required to test a program's functions

4. Ease of modifying software applications

The correct answer is: Effort required to test a program's functions

Testability refers to the extent to which a software application can be tested effectively and efficiently. It focuses on the characteristics that make testing easier, such as the clarity of the program's specifications, the functionality of its features, and the availability of test data. When considering option C, it reflects the core idea of testability by assessing the effort required to test a program's functions. Highly testable software enables testers to evaluate its functions without excessive complexity, thereby minimizing the amount of effort needed to conduct testing. In contrast, the other options do not directly relate to the concept of testability in a testing context. For example, repurposing software deals with the adaptability of the program to new use cases rather than how easily it can be tested. The preparation needed for software transfer focuses on deployment and integration aspects rather than the feasibility of testing itself. Similarly, modifying software applications speaks more to maintainability than to the inherent ease or difficulty of testing its functions. Thus, option C captures the essence of what testability means in software testing practices.