What does an inductor do in an electrical circuit?

The role of an inductor in an electrical circuit primarily revolves around its ability to store energy in a magnetic field when an electric current flows through it. Inductors are components that oppose changes in current due to this stored energy, which can be crucial in maintaining the stability and regulation of electrical signals.

When current flows through an inductor, it creates a magnetic field around it, thus storing energy in this magnetic field. This energy can then be released back into the circuit when the current decreases or is interrupted, allowing the inductor to smooth out variations or spikes in the current.

Additionally, inductors do indeed resist changes in current flow. This resistance to change in current is known as inductive reactance and forms a key aspect of how inductors function in various applications, such as filters, oscillators, and energy storage systems.

In summary, an inductor's primary functions—storing electrical energy in a magnetic field and resisting changes in current flow—combine to define its behavior in electrical circuits. Therefore, the answer encompassing all these aspects makes the choice that includes all of the functions provided the most accurate representation of an inductor's role.