In the atmosphere ultraviolet rays are absorbed by (a) Oxygen (b) Nitrogen (c) Ozone (d) Helium
option A. As daylight passes thru the atmosphere, all UVC and about 90% of UVB radiation is absorbed through ozone, water vapour, oxygen and carbon dioxide. UVA radiation is much less laid low with the atmosphere. Therefore, the UV radiation achieving the Earth's floor is basically composed of UVA with a small UVB component.
