Question

LEDs (Light Emitting Diodes) are available in many colours such as red, green, yellow, blue and white and are increasingly being used for many applications, for example in traffic signal lights. But in everyday life we use CFLs and are currently the best choice because

• A. LEDs consume more electricity
• B. LEDs are expensive
• C. LEDs do not glow for long time
• D. LEDs are harmful

Answer 1

The correct option is B LEDs are expensive

LED light sources consume less electricity and have longer lifetime than light bulbs and fluorescent tubes. But LED light sources are expensive. So CFLs are currently the best choice. However, CFLs contain mercury.