Power supplies may perform which of the following functions?

Power supplies are essential components in electrical systems, primarily designed to provide a stable voltage and current to various electronic devices. One of their key functions, particularly for devices requiring direct current (DC) operation, is the conversion of alternating current (AC) into direct current (DC) voltage. This conversion is crucial because many electronic components, such as microcontrollers and integrated circuits, operate only on DC.

In this process, the AC voltage is rectified—using diodes or other components—to produce a smoother DC output, often accompanied by regulation to maintain consistent voltage levels despite variations in load or input voltage. This function ensures that the downstream devices receive a reliable power source, which is fundamental for their proper operation.

While power supplies may also have capabilities like energy storage or signal generation, those features are not their primary functions, and not all power supplies possess those additional capabilities. Similarly, increasing impedance is generally related to circuit design and interactions between components rather than a function specific to power supplies. Thus, the most accurate choice that defines a fundamental role of a power supply is its ability to convert AC into DC voltage.