Identify the three main types of lamps (bulbs).

• A. Tungsten, Gas discharge, LED
• B. Halogen, Fluorescent, Incandescent
• C. Tungsten, Halogen, LED
• D. LED, OLED, Plasma

Answer: (A)

Lamps are grouped by the technology that produces light: tungsten (incandescent) bulbs use a heated tungsten filament; gas-discharge lamps produce light by exciting a gas inside a tube (common forms are fluorescent and other gas-discharge types); and LED lamps emit light with semiconductor diodes (solid-state lighting). These three cover the broad, practical categories used in lighting practice today: tungsten for traditional incandescents, gas-discharge for more efficient fluorescent/HID options, and LED for the modern, highly efficient category.

Halogen is just a variant of incandescent, so it doesn’t form a distinct main category. Fluorescent is gas-discharge, but grouping it with tungsten and LED gives a complete three-way split; the other options bring in technologies (like OLED or plasma) that aren’t used as standard general lighting lamp types.