You need to configure a new Cisco router to be installed in the Company VOIP network.
Which three interface commands will configure the switch port to support a connected Cisco
phone and to trust the CoS values received on the port if CDP discovers that a Cisco phone
is attached? (Select three)

A.
switchport voice vlan vlan-id

B.
mls qos trust device cisco-phone

C.
switchport priority extend cos_value

D.
mls qos trust cos

E.
mls qos trust override cos

Explanation:
1. To configure the IP Phone uplink, just configure the switch port where it connects. The
switch instructs the phone to follow the mode that is selected. In addition, the switch port
does not need any special trunking configuration commands if a trunk is wanted. If an
802.1Q trunk is needed, a special-case trunk is negotiated by Dynamic Trunking Protocol
(DTP) and CDP. Use the following interface configuration command to select the voice
VLAN mode that will be used:
Switch(config-if)# switchport voice vlan { vlan-id | dot1p | untagged | none}

2. mls qos trust [cos] : Configure the port trust state.
By default, the port is not trusted. All traffic is sent through one egress queue. Use the cos
keyword to classify ingress packets with the packet CoS values. The egress queue assigned
to the packet is based on the packet CoS value
3. mls qos trust device cisco-phone : Configure the Cisco IP Phone as a trusted device on
the interface.