Final answer:
William James would be interested in exploring how test-taking anxiety serves as an adaptive function that could potentially enhance academic performance, using both introspection and objective measures for assessment.
Step-by-step explanation:
William James, given his functionalist views, would likely be most interested in a research question related to test-taking anxiety that examines how this anxiety serves an adaptive function in an organism's environment. Specifically, he might research how test-taking anxiety might motivate students to prepare more thoroughly for exams, thus improving their performance and leading to better academic outcomes.
James would approach this by looking at how the mental activity of anxiety contributes to a student's ability to adapt and succeed in their educational environment. Moreover, he would make use of both introspective methods as well as more objective measures to assess the function of anxiety in this context.