Refer to the exhibit.  Which two statements are true about the required switch configurations to  support a voice VLAN？（）

• A、CDP must be disabled on the switch port to prevent interference between CDP messages and  voice traffic.
• B、Port security cannot be configured on a port that is configured for a voice vlan.
• C、Static secure MAC addresses should be configured on voice vlan ports to prevent access by  devices other than IP phones.
• D、CDP must be enabled on the switch port to allow configuration information to be passed to the  IP phone.
• E、Portfast must be enabled on the switch port.
• F、802.1x authentication cannot be configured on a port configured for a voice vlan.