Which IOS feature provides dial plan scalability and bandwidth management for H.323 VoIP implementations？（）

A.the packetization size
B.the serialization of the interface
C.the quantization
D.the packet rate
E.the UDP overhead
F.the TCP overhead

A.service guarantee
B.traffic that is divided into classes
C.not scalable to large implementations
D.QoS mechanisms that are used without prior signaling
E.applications that signal their particular QoS and bandwidth requirements

A.WLAN controllers
B.WLAN Solution Engine （WLSE）
C.Cisco Wireless Control System （WCS）
D.Cisco Wireless Location Appliance
E.lightweight access point （AP）
F.autonomous access point （AP）