With unmanaged CE routers, at which point in the service provider network is the QoS trust boundary, and what is required at the trust boundary?
A . between the CE and PE router and mapping of the customer traffic classes into the service provider traffic classes at the PE router ingress
B . between the CE and PE router and trusting the QoS markings from the CE router and applying the required QoS mechanisms based on the customer QoS markings
C . between the PE and the P router and mapping of the customer traffic classes into the service provider traffic classes at the P router ingress
D . between the PE and P router and trusting the QoS markings from the CE router and applying the required QoS mechanisms based on the customer QoS markings
E . between the customer network and the CE router ingress and applying the required egress QoS policy on the CE router
Answer: A