Which component would be considered part of a "basic" power supply?

A basic power supply typically includes a diode rectifier as a fundamental component. The role of the diode rectifier is crucial because it converts alternating current (AC) into direct current (DC), which is necessary for many electronic circuits. This conversion is one of the primary functions of a power supply, making the diode rectifier an essential element.

In contrast, while a resistor is often used for current limiting or voltage division, it does not perform the essential task of converting power. A transistor can act as an amplifier or a switch but is not a necessary component for basic power supply functionality. An inductor may be utilized in more complex power supply designs, such as in filtering applications, but it is not a defining part of what constitutes a basic power supply. The simplicity and fundamental nature of the diode rectifier in the process of power conversion is the reason it's identified as a key component in a basic power supply.