Your question is Ensuring A/B Test Validity. 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 strategies would you use to ensure the validity of your A/B test results?
Address the complete experimentation lifecycle without assuming a particular product or metric. Explain how you would define the hypothesis and metrics, choose randomization and analysis units, calculate sample size using an explicit MDE, monitor experiment quality, and prevent invalid conclusions from peeking, novelty, multiple comparisons, or sample ratio mismatch.
Provide a practical analysis and decision plan, including guardrails and actions for significant, insignificant, or anomalous results.