The Ajax network coordinator is concerned that the IP phones can be targeted for malicious attack. When the security is designed for the IP telephony solution, which two methods can be used to help prevent malicious phone attacks? (Choose two.)

A.
Ensure the PC port is disabled if a PC is not attached.

B.
isolate the IP phone VLANs from the PC data VLANs.

C.
Ensure the IP phone firmware is validated with the Cisco Unified Communications Manager.

D.
Ensure the Cisco Unified Communications Manager is configured to disable acceptance of GARP on IP phones.