Assertion (A): Chlorofluorocarbons are responsible for ozone depletion.
Reason (R): Ozone level decreases by as much as 67% every year.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
Explanation:
Stratosphere zone of Earth's atmosphere contains a layer of ozone which protects us from harmful ultraviolet radiations of the sun. A group of chlorine containing compounds called chlorofluorocarbon (CFCs) used as coolants in air conditioners and refrigerators are primary chemicals responsible for ozone depletion. After their release into troposphere, CFCs go to stratosphere where they are broken down by UV radiations releasing chlorine. In presence of sunlight, chlorine breaks O3 into O2. Due to ozone depletion, its levels decreases by 67% every year causing higher levels of UV radiations reaching earth which may cause eye cataracts, skin cancer etc.