Which of the following components can consist of three regions of semiconductor material?

• A. Diode
• B. Resistor
• C. Transistor
• D. Capacitor

Answer: (C)

A transistor is a semiconductor device that can indeed consist of three regions of semiconductor material. These regions typically include two p-n junctions, which allow the transistor to function as an amplifier or a switch. The three regions are often referred to as the emitter, base, and collector.

In a bipolar junction transistor (BJT), the three layers of doped semiconductor material are arranged in one of two configurations: NPN or PNP. These configurations play a critical role in the transistor's ability to control electrical signals and perform various electronic functions.

The other components listed—diodes, resistors, and capacitors—do not have a three-region structure. A diode consists of a single p-n junction, resistors are passive components that oppose the flow of current but do not have semiconductor regions, and capacitors store electrical energy in an electric field and are composed of conductive plates separated by an insulating material. Thus, only the transistor fits the description of having three regions of semiconductor material, highlighting its importance in electronic circuits.