What type of security control requires validating a user's physical characteristics?

• A. Password authentication
• B. Biometrics
• C. Smart cards
• D. Two-factor authentication

Answer: (B)

The correct choice is biometrics, which refers to the use of an individual's physical characteristics to verify their identity. This can include features such as fingerprints, facial recognition, iris scans, or voice recognition. The fundamental principle behind biometric authentication is that these unique physical attributes are difficult to replicate, making this method a strong security control.

Biometrics enhances security significantly because it relies on something inherent to the individual, as opposed to something they know or possess, which can be forgotten or stolen. It ensures that access is granted only when a user's physical traits match stored data, providing a higher level of confidence in the identity verification process.

Other options represent different types of security controls, but they do not involve physical characteristics. Password authentication relies on knowledge (something the user knows), smart cards rely on possession (something the user has), and two-factor authentication is a combination of different factors, often involving something the user knows and something they have. None of these options utilize biometric data, which is why biometrics is specifically identified as the correct choice.