The core issue is the test automation tool's inability to identify GUI elements from third-party components. The most logical and professional first step in investigating this is to determine the component's inherent testability. This involves checking the component's documentation or contacting the vendor directly to inquire about automation support, known issues, or required configurations. This approach targets the root cause—whether the component was designed to be automatable. It is a direct and efficient investigation into the specific technology that is failing, which is a key responsibility of a Test Automation Engineer when dealing with external dependencies.

B. The application is described as "standalone," making a browser dependency unlikely. This would not be the primary line of investigation for an issue specific to third-party components.

C. Using coordinates is a brittle, last-resort workaround, not an investigation step. Adopting this approach first bypasses root cause analysis and leads to a non-maintainable solution.

D. Internal naming standards for automation variables have no impact on the external test tool's ability to recognize and interact with the application's GUI elements.

1. ISTQB® Certified Tester Advanced Level Test Automation Engineer Syllabus Version 1.0 (2019).

Section 4.3.1, SUT Testability, states: "For third-party controls, this may involve contacting the vendor for a version of the control that is compatible with the test automation tool, or for information on how to use the control with the test automation tool." This directly supports option A as a standard procedure.

Section 4.4.2, Designing the TAS (GUI-based TAS), notes: "Identification by coordinates should only be used when other methods are not possible, since this approach is very sensitive to changes in the GUI layout." This explicitly positions the method in option C as a last resort, not a first step.