What technology is considered an example of two-factor authentication?

Two-factor authentication (2FA) enhances security by requiring two different forms of verification to gain access to an account or system. The correct answer involves using something you know (a password) combined with something you have (a text message code).

In this case, when a user attempts to log in, they first enter their password, which represents the knowledge factor. Then, they receive a one-time code via text message, which serves as the possession factor. This combination significantly improves security, as even if someone steals your password, they would still need access to your mobile device to complete the login process.

The other options represent either single-factor authentication or methods that lack the necessary separation between the two factors. For instance, using only a username and password relies solely on what the user knows, while password and security questions still fall under a single factor since both elements are knowledge-based. Similarly, a fingerprint and password could potentially represent two factors, but they are typically viewed within the context of biometric authentication combined with knowledge; they do not include the critical aspect of a second factor that is received through an external channel, like a text message.