Final answer:
An example of two-factor authentication is the combination of a user's fingerprint and a personal Identification number, which uses two different types of credentials: something the user is and something the user knows.
Step-by-step explanation:
The student has asked which of the following is an example of two-factor authentication:
- A. The user's facial geometry and voice recognition.
- B. The user's password and a separate passphrase.
- C. The user's key fob and a smart card.
- D. The user's fingerprint and a personal Identification number.
Two-factor authentication (2FA) is a security process in which the user provides two different authentication factors to verify their identity. This method adds an additional layer of security to the standard single-factor authentication, which is typically a password. Example D, which combines a fingerprint (something the user is) and a personal Identification number (something the user knows), is a classic example of two-factor authentication as it uses two distinct types of credentials.