Which of the following are authorization techniques that seek to prevent hackers from gaining access to a system?

The correct answer is A. smart cards, key fobs, or biometric identification.

These are all methods of authorization that enhance security by verifying the identity of users before granting them access to a system. Smart cards and key fobs use physical devices, while biometric identification relies on unique personal attributes, such as fingerprints or facial recognition, making it harder for unauthorized users to gain access.

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