Which of the following is NOT used as a primary authentication factor?

The concept of primary authentication factors revolves around methods used to verify a user's identity when they attempt to access a system or service. The three commonly recognized primary authentication factors are:

1. Something you know: This typically refers to passwords or PINs.
2. Something you are: This involves biometric data such as fingerprints, facial recognition, or retina scans, which are unique to an individual.
3. Something you have: This includes physical items like smart cards, security tokens, or mobile devices that can generate authentication codes.

The option identified as not being a primary factor is "somewhere you are," which typically refers to geolocation or time-based contextual factors used in security, often as supplementary measures rather than as standalone authentication methods. While location can offer additional security (like restricting access based on geographic location), it does not serve as a primary means of authenticating an individual’s identity, making it distinct from the established categories of authentication factors.