Explain how a p-n junction diode operates as a rectifier, as a solar cell, and as a LED.
a) It conducts current in one direction only, absorbs light to produce electricity, and emits light when forward-biased.
b) It conducts current in both directions, absorbs light to produce electricity, and emits light when reverse-biased.
c) It conducts current in one direction only, absorbs light to produce electricity, and emits light when reverse-biased.
d) It conducts current in both directions, absorbs light to produce electricity, and emits light when forward-biased.