Data routing primitives: which combinational logic device takes data from a single input source and routes it to one of several outputs (one-to-many) under control selection?

Introduction / Context:
Multiplexers (MUX) and demultiplexers (DEMUX) are complementary. A MUX selects one of many inputs to a single output (many-to-one). A DEMUX does the reverse: from a single input, it drives one of many outputs (one-to-many) based on select lines.

Given Data / Assumptions:

• Single data input, multiple output lines.
• Select lines determine which output carries the input data.
• Combinational (no internal memory).

Concept / Approach:
By definition, a demultiplexer fans out a single input to one of several outputs under digital control. This makes it ideal for time-division distribution, address decoding variants, and signal routing in communication buses.

Step-by-Step Solution:

Verification / Alternative check:
Truth tables for DEMUX devices (e.g., 1-to-4, 1-to-8) confirm one-hot output selection per select code with input replicated to the chosen output.

Why Other Options Are Wrong:

Common Pitfalls:
Confusing decoders and demultiplexers; while related, a decoder does not forward the data stream, it only asserts selection lines.

Final Answer:
demultiplexer