Ozone prevents the entry of

Options

(a) infrared rays
(b) visible rays
(c) UV rays
(d) X-rays

Correct Answer:

UV rays

Explanation:

Ozone layer or shield is present in stratosphere which is also called ozonosphere. It lies at an altitude of 23-25 km over equator and its concentration is 300 dobsons. It functions as a shield against strong UV radiations. Protection from UV radiations is proportional to thickness of ozone layer. Depletion in the concentration of ozone over a restricted area as spring time decline over Antartica is called ozone hole. Thinning of ozone layer increases the amount of UV-B radiations reaching the earth. It would increase occurence of cataracts, skin cancers, herpes, dimming of eye sight, photoburning, deficient functioning of immune system.