Your question is White-Box vs Black-Box Testing. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You're discussing test strategy for a new engineering initiative and want to explain when different testing approaches are appropriate during execution.
Can you explain the difference between white-box testing and black-box testing, and how you would decide when to use each?