Answer:
C. The objective test provides specific, non-subjective information about risk-taking tendencies while the unstructured interview allows for deeper explanations of the thought processes behind that information.
Step-by-step explanation:
If a therapist is interested in measuring her client's propensity for taking risks and decides to use both an objective test for the trait of risk-taking and an unstructured interview.
The best argument that would best defends her choice would be that the objective test provides specific, non-subjective information about risk-taking tendencies while the unstructured interview allows for deeper explanations of the thought processes behind that information.
Please note that objective test has to do with true or false answers, while unstructured interview is one that isn't planned and flows spontaneously based on answers received.