What electrical parameter is controlled by a potentiometer?

A potentiometer is a variable resistor and is primarily used to control resistance within a circuit. When you adjust the knob or slider on the potentiometer, it changes the position of a resistive element within it, effectively varying the resistance value. This adjustment can influence many aspects of an electrical circuit, such as adjusting the volume in audio equipment or dimming lights.

Inductance, capacitance, and field strength are directly related to different components and properties in electrical circuits. Inductance pertains to coils and magnetic fields, capacitance relates to capacitors and the ability to store electric charge, and field strength is associated with the intensity of an electric or magnetic field. These parameters are not directly altered by using a potentiometer, which is specifically designed to manipulate resistance. Thus, the correct answer focuses on the fundamental operation of a potentiometer as a device for varying resistance.