What type of authentication combines something you know with something you have?

The correct answer is multi-factor authentication. This method enhances security by requiring two or more different types of authentication factors from the user before granting access. These factors typically include:

1. Something you know – such as a password or a PIN.

2. Something you have – like a physical token, smart card, or a mobile device that receives a one-time code.

By combining these elements, multi-factor authentication significantly reduces the risk of unauthorized access, as it is much harder for an attacker to possess both the knowledge of the password and the physical token. This layered defense mechanism is highly effective in protecting sensitive data and systems.

Single-factor authentication relies solely on one type of credential, making it less secure. Biometric authentication uses physiological traits like fingerprints or facial recognition, which is different from the combination of knowledge and possession. Behavioral authentication monitors patterns and behaviors but does not involve distinct knowledge or possession factors.