Final answer:
The correct answer is a. LED (Light Emitting Diode), which emits a single-color light when activated. LEDs are increasingly popular for energy efficiency and the ability to produce a variety of colors and hues of white light. They are replacing traditional incandescent and CFL bulbs in most lighting applications.
Step-by-step explanation:
The electronic semiconductor that emits a single-color light when activated is the LED (Light Emitting Diode). LEDs are special types of diodes that are made of semiconducting materials infused with impurities, which allow them to convert electrical energy into visible light. Commercial LED light bulbs are increasingly replacing traditional incandescent and CFL light bulbs in both commercial and residential settings. An LED's color can vary based on the materials used in its semiconductor and the current flowing through it, enabling it to produce many different hues of white light as well as millions of other colors.
Unlike LEDs, LCD (Liquid Crystal Display) uses liquid crystals and a backlight to produce images. These crystals control the amount of light that passes through red, blue, or green filters to create the full color spectrum on the screen. CFLs, or Compact Fluorescent Lamps, on the other hand, are a different technology that uses a gas-filled tube to produce light when an electric current is passed through it.
The modern lighting industry has seen significant shifts due to the energy efficiency and longevity of LEDs. They not only save energy but also have a longer lifespan than traditional light sources. For example, a 60-watt incandescent bulb can be replaced with a 6- to 8-watt LED bulb, which also produces approximately 800 lumens of light output.