You are working with a client to deploy QoS on their Frame Relay WAN. They would like to be able to allow packets to cross the Frame Relay WAN but have them marked as discard eligible if they exceed the QoS policy. How would you accomplish this task?（）

A. Configure a class map that sets the DE bit so that the policy map can correctly apply a violate-action if the policy is exceeded.
B. Configure a service policy that sets the DE bit and apply it to the serial interface connected to the Frame Relay WA
Configure a policy map that has a burst-max action of setting the DE bit if the policy is exceeded.
D. Configure a policy map that has a violate-action to change the DE bit from 0 to 1.