What does multifactor authentication involve?

Multifactor authentication involves utilizing a combination of more than one authentication method to verify a user's identity. This approach enhances security by requiring multiple forms of verification that generally fall into three categories: something you know (like a password), something you have (like a security token or smartphone), and something you are (like a fingerprint or facial recognition).

The idea behind multifactor authentication is that even if one factor is compromised, the additional factors provide an extra layer of security. For instance, even if a password is stolen, an attacker would still need access to the second factor (like a physical token) or the biometric data to gain access.

The incorrect options do not capture the essence of multifactor authentication adequately. A single authentication method does not provide the robustness required for secure access, and relying solely on biometric authentication would neglect other viable forms of verification that enhance security.