In terms of security, which of the following comprises ?something you have ??

An ID card is a physical possession that a person must carry and present, placing it squarely in the 'something you have' authentication factor category. This factor encompasses physical tokens, smart cards, key fobs, and identity cards that grant access only to whoever holds them. Loss or theft of the card directly compromises this factor, which is a defining characteristic of physical possession-based authentication.

A user ID is a known identifier memorized or stored by the user, classifying it as 'something you know', not 'something you have'.

A password is the canonical example of 'something you know' because it is a secret memorized by the user, not a physical object.

A retina scan is a biometric identifier unique to the individual's physiology, classifying it as 'something you are', not 'something you have'.