Correct option is C
Sequential circuits are those in which the output depends not only on the current inputs but also on the past history of inputs.
These circuits have memory elements that store the state of the circuit.
Explanation of the Options:
(a) Comparator
A comparator is a combinational circuit that compares two input values and outputs a result based solely on the current inputs.
It does not have memory and does not depend on previous inputs.
(b) Encoder
An encoder is a combinational circuit that converts multiple input lines into fewer output lines.
It does not have memory and operates only on the current inputs.
(c) Counters
Counters are sequential circuits because they have memory elements (typically flip-flops) that store the count value and update it based on a clock signal.
The output of a counter depends on its previous state as well as the current input (clock pulses).
(d) Multiplexer
A multiplexer is a combinational circuit that selects one of several input signals and forwards the selected input to a single output line.
It operates based only on the current inputs and selection lines, without memory.
Therefore, the correct answer is (c) Counters.
