What does a power supply convert?

A power supply primarily converts alternating current (AC) to direct current (DC), which is essential for powering most electronic devices. Many electronic components, such as microcontrollers and integrated circuits, operate on DC voltage levels. The conversion process typically involves components like transformers, rectifiers, and filters that work together to change the incoming AC voltage to a stable, usable DC output.

Other options like converting DC to AC or AC to high frequency may describe specific types of power converters or inverters but do not represent the fundamental role of a standard power supply. Thus, the correct identification of AC to DC conversion highlights a core aspect of how power supplies function in electronic applications.