An energy efficient device for producing light is:(a) DLF (b) CFL (c) FCL (d) LPG

(b) CFL

Explanation

A "Compact fluorescent lamp" (CFL) works on the principle of ionisation. Instead of a glowing filament, it contains argon and mercury vapour housed within a spiral-shaped tube. This, make it an energy-efficient device, as it consumes much less electrical energy.