On a Cisco Catalyst Switch, which command is required to send CDP packets on a switch port that configures a Cisco IP phone to transmit voice traffic in 802.1Q frames, tagged with the voice VLAN ID 221?
A. Device(config-if)# switchport trunk allowed vlan 221
B. Device(config-if)# switchport vlan voice 221
C. Device(config-if)# switchport voice vlan 221
D. Device(config-if)# switchport access vlan 221
