What tool is used to measure electrical resistance?

A multimeter is a versatile instrument used to measure various electrical properties, including voltage, current, and resistance. When measuring electrical resistance, the multimeter typically sends a small current through the resistor and measures the voltage drop across it, then calculates the resistance using Ohm's Law (R = V/I). This capability makes the multimeter an essential tool in electrical diagnostics, allowing technicians to quickly and effectively assess the health and function of various components within a circuit.

Other tools such as an ammeter are specifically designed to measure current, while a voltmeter is used exclusively for voltage measurements. An oscilloscope visualizes voltage changes over time but does not directly measure resistance. Hence, a multimeter's multifunctional approach makes it the correct answer for measuring electrical resistance.