Which of the following best describes "multi-factor authentication"?

Multi-factor authentication (MFA) is a security mechanism that strengthens access controls by requiring users to present two or more verification factors when logging into an account or system. This approach significantly enhances security compared to single-factor authentication, which typically relies solely on a username and password.

The core principle behind MFA is that it combines something the user knows (like a password), something the user has (such as a smart card or a mobile device), and something the user is (like a fingerprint or facial recognition). This layered approach means that even if one of the factors, such as a password, is compromised, an unauthorized individual would still need to bypass the other factors to gain access, greatly reducing the likelihood of unauthorized entry.

The other options present isolated methods or misconceptions surrounding security practices. For instance, using multiple passwords for one access point does not incorporate different types of verification factors, while biometric methods alone or issuing temporary access codes do not constitute MFA unless they are combined with other forms of authentication. Therefore, the correct description of multi-factor authentication is the combination of these varied factors to bolster overall security.