Which statement correctly describes the function of a policer?

A.
It determines the amount of bandwidth allocated to a queue.

B.
It writes a value into an outbound packet’s CoS field according to the packet’s forwarding
class and loss priority.

C.
It defines a set of parameters, including transmission rate, queue priority, delay buffers,
and congestion management and avoidance.

D.
It provides a first stage of congestion management by controlling the amount of traffic
entering a device.