(A) Nitrogen
(B) Carbon dioxide
(C) Oxygen
(D) None of these
🧠 Explanation:
Electric bulbs are filled with inert gases like argon or nitrogen to prevent the tungsten filament from burning out quickly. These gases increase the bulb’s lifespan and efficiency by reducing filament evaporation. Unlike early vacuum bulbs, modern bulbs use inert gas to produce brighter light and ensure durability, making them more practical for everyday use.
