Which of the following is a benefit of API Testing?

• A. It requires a graphical user interface
• B. It is more time consuming than GUI testing
• C. It helps detect issues before GUI testing
• D. It is limited to only one programming language

Answer: (C)

API testing is a vital aspect of software development that offers numerous advantages, one of which is identifying issues before moving on to GUI testing. This is significant because when APIs are tested first, developers can catch potential bugs or errors at an earlier stage of the development process. By catching these issues upfront, it reduces the likelihood of encountering them later during GUI testing when costs are typically higher due to the additional resources and time required to rectify problems.

By focusing on the underlying functionality through API calls, QA professionals can ensure that the logic and data handling of the application are functioning as expected before the user interface is tested. This leads to more robust applications, better stability, and a smoother user experience, as issues are resolved earlier on.

The reasons behind the other choices not being correct contribute to the strength of API testing further. For example, API testing does not require a graphical user interface, which allows for faster and more efficient testing of the backend functions of an application. Additionally, API testing can often be less time-consuming than GUI testing, given that it focuses on fewer layers of the application stack. Finally, API testing is not limited to one programming language; it can be performed across various languages and platforms, making it more versatile in the realm of software testing.