What is an example of a knowledge factor used for authentication?

Understanding Knowledge Factors:

Knowledge factors are something the user knows and are commonly used for authentication.

Examples include passwords, PINs, and security questions.

Why Other Options Are Incorrect:

Option A (ID card): This is a possession factor (something you have).

Option C (Security token): A security token is also a possession factor.

Option D (Fingerprint): This is a biometric factor (something you are).