Refer to the exhibit. Why does the trust state of interface FastEthernet 0/3 show “not trusted”?

A.
DSCP map needs to be configured for VOIP.

B.
ToS has not been configured.

C.
ToS has been misconfigured.

D.
The command mls qos needs to be turned on in global configuration mode.

E.
There is not a Cisco Phone attached to the interface.