Which term refers to a representation that lists input-output mappings for a circuit?

• A. Truth table
• B. Logic circuit
• C. Logic expression
• D. High-level language

Answer: (A)

Understanding input-output mappings for a circuit is captured most directly by a truth table. This is a tabular representation that lists every possible combination of input values and shows the resulting outputs for each combination. It makes the behavior of the circuit explicit and easy to analyze, especially for verifying correctness and for deriving how outputs depend on inputs. For a circuit with n inputs, you’ll have 2^n rows, one for each possible input pattern, with the corresponding outputs in each row. This clear mapping is precisely what a truth table provides.

In contrast, a logic circuit is a diagram of gates and connections, showing how signals flow but not enumerating every input scenario. A logic expression describes outputs as algebraic relationships to inputs, which is powerful but not as immediately checkable for all input combinations. A high-level language represents behavior in programming terms, not in a direct input-output mapping for the circuit.