19. In the atmosphere ultraviolet rays are absorbed by A.Oxygen B.Nitrogen C.Ozone D.Helium
Option A Solution: As sunlight passes through the atmosphere, all UVC and approximately 90% of UVB radiation is absorbed by ozone, water vapour, oxygen and carbon dioxide. UVA radiation is less affected by the atmosphere. Therefore, the UV radiation reaching the Earth's surface is largely composed of UVA with a small UVB component.
