Which additional factor is commonly included in MFA beyond the three core factors?

• A. A biometric or contextual factor.
• B. A secondary password.
• C. A static PIN only.
• D. A single hardware token.

Answer: (A)

Multi-factor authentication strengthens security by requiring more than one category of verification. The three main categories are something you know, something you have, and something you are. Beyond these, many systems add a fourth factor that is biometric or contextual in nature—biometric uses a physical trait like a fingerprint or facial scan, while contextual (risk-based) uses information about the situation, such as device, location, or time, to decide if additional verification is needed. This extra factor further reduces risk because even if a password and a hardware token are compromised, access can still be blocked if the biometric check or contextual criteria aren’t satisfied. The other options stay within one category or reuse a single element and don’t provide that additional, distinct factor.