A capacitor opposes any change in what?

A capacitor is designed to store and release electrical energy in a circuit, and it plays a specific role when it comes to changes in voltage. When the voltage across a capacitor is changed, it resists that change by either charging or discharging. This behavior is described by the fundamental principle of capacitors: they resist sudden changes in voltage by temporarily storing charge.

When a voltage is applied across a capacitor, it creates an electric field that causes stored energy. If the voltage attempts to change quickly, the capacitor either needs to absorb or release charge to accommodate for that change, demonstrating its opposition to voltage changes. This property is why capacitors are often used for applications like filtering signals and smoothing out voltage fluctuations in power supplies.

In contrast, capacitors do not directly oppose changes in current, resistance, or inductance in the same way they do for voltage. Current changes may affect how the capacitor charges or discharges, but it is the voltage across the capacitor that primarily determines its behavior. Thus, the correct answer highlights the specific and critical role of capacitors in regulating voltage in electronic circuits.