What are three Cisco Unified CallManager features？（）

A.WRED can selectively discard lower priority traffic when the interface becomes congested and can provide differentiated performance characteristics for different classes of service.
B.Resource Reservation Protocol （RSVP） and WRED cannot be configured on the same interface.
C.WRED will throttle back voice traffic only as a last resort.
D.If the average queue length is greater than the minimum threshold but less than the maximum threshold， then based on the drop probability， WRED will either queue the packet or perform a random drop.
E.WRED statistically drops more packets from low-bandwidth users than high-bandwidth users. Therefore， traffic sources that generate the least traffic are more likely to be slowed down than traffic sources that generate the most traffic.
F. WRED treats non-IP traffic as precedence 4.

A.SDMVoice
B.SDMSignal
C.SDMTrans
D.SDMManage
E.SDMRout
F.SDMBulk

A.Traffic bursts are smoothed out by queuing the excess traffic to produce a steadier flow of data
B.Excess traffic is buffered so that the traffic remains within the desired rate.
C.Packets that conform to traffic policies are not delayed.
D.Packet marking is available and allows excess packets to be re-marked with a lower priorit