Select the correct arrangement of the types of ultraviolet radiations according to the intensity of their effect on human skin

Options

A. `UV-A gt UV-B gt UV-C`
B. `UV-B gt UV-C gt UV-A`
C. `UV-C gt UV-B gt UV-A`
D. `UV-A gt UV-C gt UV-B`

Answer

B

Explanation

Ultraviolet radiations are of three types -UV-C (100-280 nm), UV-B (280-320 nm) and UV-A (320-390 nm). Shorter ultraviolet radiations (UV-C) ar absorbed by the atmosphere. The longer ones are not much hjarmful. The intermediate or UV-B are harmful as well as capable of deep penetration. Thinning of ozone layer increases the amount of UV-B radiations reaching the earth. UV-B radiations damage skin cells cause ageing of skin and skin cancer.