Which value is measured in a de-energized circuit?

In a de-energized circuit, the measurement that can be accurately taken is resistance. Resistance is the property of a material that opposes the flow of electric current, and it is measured in ohms. Since a de-energized circuit means that there is no voltage present and, consequently, no current flowing, it is not possible to measure voltage, current, or power in that state.

When taking resistance measurements, a multimeter applies a small test voltage to the circuit and measures how much current flows in response, allowing it to calculate the resistance using Ohm's Law (R = V/I). This process does not require the circuit to be energized, making resistance measurement safe and appropriate in this context.

Other choices involve operational conditions not present in a de-energized circuit: voltage would equal zero, current would also equal zero, and power, which is the product of current and voltage, would therefore also be zero.