Your question is Diagnose Engagement Drop. 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).
What methods would you use to diagnose a drop in user engagement metrics over a quarter?
Explain how you would validate the metric, isolate the source of the decline, distinguish behavioral changes from tracking or data-quality issues, and determine what actions to recommend. Discuss the analyses, segments, comparisons, and supporting metrics you would use.