Refer to the exhibit.

On an 802.1Q trunk, the native VLAN is the VLAN whose traffic is sent untagged. If the administrator wants VLAN 67 to be untagged while all other VLANs remain tagged, the trunk native VLAN must be changed to 67. The correct command is switchport trunk native vlan 67. Setting switchport access vlan 67 would affect an access port, not trunk tagging behavior. switchport trunk allowed vlan 67 would restrict which VLANs are permitted over the trunk rather than making VLAN 67 untagged. A private VLAN association command is unrelated to 802.1Q trunk native VLAN handling. Cisco CCNA 200-301 v1.1 Network Access expects engineers to understand the difference between access VLANs, allowed VLAN lists, and native VLANs. The native VLAN must match on both sides of the trunk to avoid VLAN leakage and inconsistent forwarding. Here the requirement is explicitly about untagged trunk traffic, so D is the only precise command.