question_answer

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With reference to CFL bulbs, consider the following statements.

1. Unlike other bulbs, CFL are consumer friendly and don't pose health hazard,

2. The luminous efficacy of a typical CFL is 50-70 lumens per watt (1m/w) and that of a type incandescent lamp is 10-17 lm/w.

3. The luminous efficacy of lamps is the number of lumens produced for each watt of electrical power used.

4. CFLs emit light from a mix of phosphorus inside the bulb each emitting one band of colour.

Which of the statements given above are correct?

A)  1 and 4           

B)  2, 3 and 4          

C)  3 and 4           

D)  All of these