The correct answer is C. multiplexer.
A multiplexer (MUX) is a combinational logic circuit that selects one of several input signals and forwards it to the output. The selection is made by a control signal.
A decoder is a combinational logic circuit that converts a code into a set of outputs. The code can be a binary number, a Gray code, or any other type of code.
An encoder is a combinational logic circuit that converts a set of inputs into a code. The code can be a binary number, a Gray code, or any other type of code.
A demultiplexer (DEMUX) is a combinational logic circuit that takes one input signal and routes it to one of several outputs, depending on the value of a control signal.
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