Which characteristic is true of black box testing?

Black box testing is a software testing method focused on evaluating the functionality of an application without any knowledge of its internal workings. The correct answer emphasizes that this testing approach is indeed feasible for simple applications.

In black box testing, testers concentrate on providing inputs and examining outputs based on the specifications of the software. This method doesn't require understanding of the source code or internal logic, making it appropriate for a wide variety of applications, including simpler ones. By allowing testers to evaluate the software solely based on what it is supposed to do from a user's perspective, it provides valuable insights into usability and overall user experience.

While other options suggest requirements that do not align with black box testing principles, they highlight misconceptions. Black box testing does not need source code access, as it's about the user experience, not the underlying code structure. It is also unrelated to either system complexity or a lack of necessity for input and output evaluation; input and output assessment is fundamental to the testing process in this context. Thus, the idea that black box testing is suitable for simple applications accurately captures the essence of this methodology.