What is the Cisco recommended setting for the Cisco Unified Wireless Network WLC Voice Call Admission Control Max RF Bandwidth to support the Cisco Unified Wireless IP Phone 7921G?（）

A.nominally 30 percent to best align with Cisco Unified Communications System recommendations
B.100 percent to ensure that the VoWLAN calls can use all the available bandwidth, if needed
C.system default of 75 percent
D.40 to 60 percent
E.voice CAC should be left disabled unless wired QoS is configured