Comprehensive and Detailed Explanation (aligned to N10-009):
802.1X provides port-based Network Access Control (NAC), requiring authentication (often through RADIUS) before granting access. This is the standard for enterprise authentication on both wired and wireless networks.
A). 802.1Q defines VLAN trunking.
C). 802.3bt defines higher-power PoE.
D). 802.11h deals with spectrum management in wireless.
References (CompTIA Network+ N10-009):
Domain: Network Security - NAC, 802.1X authentication.