Which set lists the four common authentication factors?

• A. Something you know; Something you have; Something you are; Something you do
• B. Something you touched; Something you read; Something you can hear; Something you own
• C. Something you can see; Something you can smell; Something you feel; Something you bend
• D. Something you predict; Something you hope; Something you think; Something you recall

Answer: (A)

Authentication relies on four common factors that people can prove to a system: something you know, something you have, something you are, and something you do. Something you know is like a password or PIN. Something you have is a physical device or token, such as a smart card or authenticator app. Something you are refers to biometric traits, such as a fingerprint or iris scan. Something you do involves behavioral patterns, like how you type or how you interact with your device.

This four-factor framing is the best match because it covers distinct, verifiable ways a user can be proven secure access without relying on just one type of credential. The other sets described mix senses, actions, or mental states that aren’t reliable, standard methods for authentication: they don’t map cleanly to verifiable categories used in practice, so they’re not the established way to categorize factors.