How would you answer an interview scenario involving multi-factor authentication?

In an interview, I would first define multi-factor authentication and the problem it solves, then explain how I would prefer phishing-resistant factors where feasible, protect enrollment and recovery flows, support step-up authentication for sensitive actions, monitor suspicious changes, and avoid weak fallback paths. I would also call out the main failure mode: strong MFA can be undermined if account recovery relies only on easily compromised email, SMS, or knowledge questions without equivalent protection. Finally, I would describe how I would test, monitor, and safely roll back or recover the solution.