Which authentication method requires more than one factor to verify a user's identity?

Which authentication method requires more than one factor to verify a user's identity?

• A. Single Sign-On
• B. Password-Only Authentication
• C. Biometric Verification
• D. Multi-Factor Authentication

Answer: (D)

Requiring more than one authentication factor to verify identity. Multi-Factor Authentication uses at least two distinct factors from categories such as something you know (password), something you have (a hardware token or mobile authenticator), and something you are (biometrics). This layered approach makes it much harder for attackers because stealing or guessing just one factor isn’t enough to gain access. For example, even if a password is compromised, a second factor is still required. The other options rely on a single factor (like password-only authentication) or address usability and access across apps rather than enforcing multiple factors (Single Sign-On and biometrics alone can be single-factor unless combined with another factor). Therefore, the method that requires more than one factor is Multi-Factor Authentication.

Requiring more than one authentication factor to verify identity. Multi-Factor Authentication uses at least two distinct factors from categories such as something you know (password), something you have (a hardware token or mobile authenticator), and something you are (biometrics). This layered approach makes it much harder for attackers because stealing or guessing just one factor isn’t enough to gain access. For example, even if a password is compromised, a second factor is still required. The other options rely on a single factor (like password-only authentication) or address usability and access across apps rather than enforcing multiple factors (Single Sign-On and biometrics alone can be single-factor unless combined with another factor). Therefore, the method that requires more than one factor is Multi-Factor Authentication.