Which of the following is a type of NAC that uses a set of policies...

802.1X is a port-based Network Access Control (NAC) method that enforces authentication before allowing access to the network. It uses a RADIUS server for identity verification and policy enforcement, ensuring only authorized users/devices gain access.

A. Standard ACL filters traffic by IP, not identity.

B. MAC filtering controls devices by hardware address but can be spoofed.

D. SSO (Single Sign-On) provides user convenience across services, not network-level access control.

References (CompTIA Network+ N10-009):

Domain: Network Security — NAC, 802.1X authentication, identity-based access.