Which three characteristics of the traffic flow are taken into consideration when the QoS-for-VPNs feature （QoS pre-classify） provides packet classification and applies appropriate QoS service on tunnel interfaces？（）

A.WCS
B.WLSE
C.WLC
D.WDS
E.LWAPP

A.aggregation congestion occurring at the core layer where the different distribution layer devices feed traffic to the core-layer switches
B.speed mismatches when moving from a low-speed LAN environment to a higher speed WAN environment
C.flapping Ethernet interfaces caused by misconfigured LAN interfaces
D.flapping serial interfaces caused by misconfigured WAN interfaces
E.speed mismatches when moving from a high-speed LAN environment to a lower speed WAN environment

A.over leased lines， use the multilink ppp command to reduce latency and jitter， and to create Distributed Link Fragmentation and interleaving
B.use the service-policy command to attach a traffic flow to an interface on the router
C.use the ip rsvp bandwidth command to set a strict upper limit on the bandwidth NBAR uses， and to guarantee admission of any flows
D.use the policy-map command to define one or more QoS policies （such as shaping， policing， and so on） to apply to traffic defined by a class map
E.use the random-detect dscp command to modify the default minimum and maximum thresholds for the DSCP value
F.use the class-map command to define one or more traffic classes by specifying the criteria by which traffic is classified