How do 2FA and MFA differ?

• A. 2FA uses exactly two factors; MFA uses three factors
• B. 2FA uses two factors and MFA uses exactly two factors
• C. 2FA uses two factors; MFA can use two or more factors
• D. 2FA uses one factor; MFA uses two or more factors

Answer: (C)

Authentication relies on proving something about the user through factors. Two-factor authentication uses exactly two factors from different categories (for example, something you know and something you have). Multi-factor authentication is the broader idea of needing at least two factors, and it can be two or more.

So a login with a password and a code from an authentication app is two-factor authentication. If you add a biometric check or a hardware key on top, it becomes multi-factor authentication with more than two factors. That’s why this option is best: it correctly states that two factors define 2FA, while MFA encompasses two or more factors.