Your question is Covariance vs Correlation. 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).
Difference between covariance and correlation?
Asked in the Technical stage. Explain the mathematical and practical distinction, including scale, interpretation, and the relationship between the two measures. Then apply the distinction to an A/B test: define an estimand, choose an appropriate primary metric, calculate an illustrative sample size, and explain how you would analyze the result without confusing association with causal impact.