What does the unit 'Ohm' measure?

The unit 'Ohm' measures resistance in an electrical circuit. Resistance is a fundamental property that determines how easily electric current can flow through a conductor. It is defined as the opposition to the flow of electric current, and it is influenced by the material, length, and cross-sectional area of the conductor.

In the context of Ohm's Law, which states that voltage equals current multiplied by resistance (V = I × R), resistance is the factor that dictates how much current will flow for a given voltage. Therefore, when we refer to Ohms, we are specifically talking about the measure of that opposition, making Option C the correct answer.

Electric current, voltage, and power are related concepts, but they are measured in different units: current is measured in Amperes (A), voltage in Volts (V), and power in Watts (W). Understanding resistance and its measurement in Ohms is crucial for analyzing and designing electrical circuits effectively.