Ohm's Law Circuit Setup Steps:

• Identify the resistor as the component where current (I) and potential difference (V) need measurement.
• Place ammeter in series with the resistor to measure current without altering the circuit path.
• Connect voltmeter in parallel across the resistor terminals to measure pd without drawing significant current.
• Ensure the circuit includes a power source and switch for safe operation.

Why A is correct:

• Ammeter in series and voltmeter in parallel align with definitions: ammeter measures current flow (low resistance), voltmeter measures pd (high resistance), enabling V = IR verification.

Why the others are wrong:

• B: Ammeter in parallel shorts the resistor, giving incorrect high current reading.
• C: Voltmeter in series disrupts pd measurement across the resistor alone.
• D: Both instruments in series measure total circuit values, not resistor-specific I and V.

Final answer: A