You are developing a CoS policy for a service provider core network that In this scenario, which three statements are correct? (Choose three.)

You are developing a CoS policy for a service provider core network that In this scenario, which three statements are correct? (Choose three.)
A . Core routers should use a common set of per-hop behaviors.
B . Core routers should use shapers to ensure that customer traffic does not exceed allowed bandwidth.
C . Core routers should use policers to ensure that customer traffic does not exceed allowed bandwidth.
D . Core routers should use a consistent CoS configuration across the network.
E . Core routers should use the DSCP markings already set on ingress traffic.

Answer: A,C,E