Design a sequential circuit with two flip-flops A and B and one input X. When X = 0, the state of the circuit remains the same. When X = 1, the circuit goes through the state transitions from 00 to 10 to 01 to 11, back to 00, and then repeats. Show the state transition by 7-segment display decoder using a. D-Flip Flop-Section B b. T-Flip Flop-Section A c. JK-Flip Flop-Section B d. RS-Flip Flop-Section A