How does virtual output queuing (VoQ) help switches avoid head-of-line blocking and enhance throughput?

A.
It divides each port ingress queue into different queues based on the priority and egress port of each packet

B.
It establishes a matrix of connections to multiple cross-bar switches within the switch backplane

C.
It considers traffic congestion, queues traffic, and informs the ingress port when it can use the crossbar

D.
It allows the ingress port to fragment packets and send the fragments in multiple queues over different
crossbars

Explanation:
A Virtual Output Queue (VOQ) is the technique used in input-queued switches where rather than keeping all
traffic in a single queue, separate queues are maintained for each possible output location. It addresses a
common problem known as head-of-line blocking.
In VOQ each input port maintains a separate queue for each output port. It has been shown that VOQ can
achieve 100% throughput performance with an effective scheduling algorithm. This scheduling algorithm should
be able to provide a high speed mapping of packets from inputs to outputs on a cycle-to-cycle basis
https://en.wikipedia.org/wiki/Virtual_Output_Queues