You have configured an AOS-CX switch to implement 802.

Voice Role VLAN Configuration:

When VoIP phones are authenticated and assigned to the "voice" role, VLAN 12 should be explicitly defined as an allowed trunk VLAN within the role configuration.

The VLAN configuration should be role-specific rather than on the edge port, as this ensures dynamic VLAN assignment based on authentication results.

Option Analysis:

Option A: Incorrect. Native VLANs are for untagged traffic, but VoIP traffic is tagged.

Option B: Correct. VLAN 12 must be configured as the allowed trunk VLAN in the "voice" role to tag VoIP traffic correctly.

Option C: Incorrect. Configuring VLAN 12 in both edge port and role settings is redundant and unnecessary.

Option D: Incorrect. Native VLANs do not handle tagged traffic like VLAN 12 for VoIP phones.