Which circuit characteristics are essential for troubleshooting electrical circuits?

The essential circuit characteristics for troubleshooting electrical circuits primarily include voltage, current, and resistance.

Voltage is critical because it represents the potential difference that drives current through the circuit. By measuring the voltage at various points, a technician can determine whether the components are receiving adequate power.

Current is also vital since it represents the flow of electric charge through the circuit. If the current is too high or too low compared to expected values, it can indicate problems such as shorts or open circuits.

Resistance is important because it helps identify the health of circuit components and connections. An unexpected change in resistance can reveal malfunctioning components or broken connections, which are crucial clues during troubleshooting.

The other options contain characteristics that, while relevant, do not encompass the core elements required for effective troubleshooting. For example, while power relates to the energy consumption of the circuit, it's not as fundamental to initial troubleshooting as voltage, current, and resistance. Similarly, while capacitance and impedance can be important in certain contexts, they are not universally essential for general troubleshooting tasks.