Question

Why is tongston used for filament of electric lamps or electric bulbs

Answer 1

(1)Original and pure tungsten has some amazing properties including the highest melting point (3695 K), lowest vapour pressure, and greatest tensile strength out of all the metals.Because of these properties it is the most commonly used material for light bulb filaments.
(2) generally the resistivity of alloys is more than the metals, that's why alloys are used
(3)In series circuits voltage is divided. Each component of a series circuit receives a small voltage so the amount of current decreases and the device becomes hot and does not work properly. Hence, series arrangement is not used in domestic circuits. 

Answer 2

due to the high ignition temperature of tungsten