Final answer:
The most likely benefit of using a test execution tool is to easily run regression tests, as these tools automate the test execution process, allowing for frequent repetition to verify no new changes have broken existing features.
Step-by-step explanation:
The question pertains to the benefits of using a test execution tool in the context of software testing. When considering the options given, it is clear that the most likely benefit of utilizing a test execution tool is D. It is easy to run regression tests.
This is because such tools are designed to automate the process of executing predefined test cases, which is particularly useful for regression testing where tests need to be repeated frequently to ensure that recent changes haven't affected existing functionalities.
On the other hand, options A, B, and C are less likely to be the direct benefits of test execution tools.
While these tools can support regression test creation (A), they are generally not specific to maintenance of version control (B) or the design of security tests (C), as these tasks require different sorts of tooling and strategies.