Correct Option: D

Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that’s how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo). In 1906, the tungsten filament was introduced. Tungsten metal was initially not available in a form that allowed it to be drawn into fine wires. Filaments made from sintered tungsten powder were quite fragile. The advantage of the coiled coil is that evaporation of the tungsten filament is at the rate of a tungsten cylinder having a diameter equal to that of the coiled coil.