Suppose a router has n input ports each with identical line speeds, n output ports each with identical line speeds, and the line speed of an output port is at least n times as that of an input port. Further suppose that the switching fabric speed is at least n times as fast as an input line speed. Then A. queuing can occur in an input port B. there is no queuing delay in the router C. queuing can occur in the switching fabric D. queuing can occur in an output port