Which of the following types of capacitors is commonly used in power supply applications?

In power supply applications, different types of capacitors each have their unique roles, but electrolytic capacitors are the most commonly utilized. They are favored for their ability to store large amounts of energy in a compact space and are designed for tasks such as filtering and smoothing voltage levels.

Ceramic capacitors are also used in power supplies but are typically employed in applications requiring low capacitance values and high-frequency response. Film capacitors are known for their stability and low losses or noise, which makes them suitable for filtering and coupling applications within a power supply.

While electrolytic capacitors dominate in terms of bulk energy storage, the effectiveness of ceramic and film capacitors in different scenarios demonstrates that all three types can contribute to power supply functionalities. Therefore, it's correct to conclude that all the mentioned types of capacitors can be used in power supply applications, thus justifying the selected answer encompassing all options presented.