Design a sequential circuit that checks whether two 4-bit numbers are equal or not. The design should be based on: Three 4-bit shift registers A single XNOR gate A single AND gate A single D flip-flop A single LED One of the shift registers should have its output connected to the LED. This shift register should be storing initially four zeros. This shift register should cause the LED to turn ON if the 4-bit numbers are equal. Otherwise, the LED turns OFF. You should briefly explain your design and show how you thought about it.