Answer:
Infrared Wavelength
Explanation:
It is because the most long range wavelength i n this case will be the infrared wavelength that has a heating effect on bodies when exposed for a longer period of times. Similarly, the visible wavelength of light is also involved. The defective parts in the fireplace will allow the escape of these infrared wavelength radiations. This heating effect can cause fire near the fire place where the defective fireplace is placed without modifications.