What is a key feature of two-factor authentication?

A key feature of two-factor authentication is the use of multiple forms of verification to enhance security. Using biometric scanning as one form of identification exemplifies this concept effectively. Two-factor authentication relies on something you know (like a password) in conjunction with something you have (like a smartphone) or something you are (like a fingerprint). By integrating biometric scanning, systems can utilize unique physical characteristics for identification, thus strengthening the verification process and making unauthorized access significantly more difficult.

Other options do not accurately capture the essence of two-factor authentication. For instance, requiring a password reset every month relates more to password management policies rather than authentication methods themselves. The assertion that two-factor authentication can only be used on mobile devices is misleading; it is applicable to various platforms, including web services and desktop applications. Finally, while many implementations of two-factor authentication do not require internet access for each component (like using an authenticator app), the general concept is not inherently tied to that requirement. Therefore, utilizing biometric scanning as a verification method aligns most closely with the objectives and functionalities of two-factor authentication.