Question

In the following question a statement of Assertion (A) followed by a statement of Reason (R) is given. Choose the correct option out of the choices given.
Assertion (A): Ozone is destroyed by solar radiation in the upper stratosphere. Reason (R): Thinning of the ozone layer allows excessive UV radiations to reach the surface of earth.

• A. Both A and R are correct and R is the correct explanation of A.
• B. Both A and R are correct but R is not the correct explanation of A.
• C. A is not correct but R is correct
• D. Both A and R are not correct.

Answer 1

The correct option is C A is not correct but R is correct

Ozone is produced in the stratosphere as UV rays(solar radiations) act on $O_2$ molecules. But, the major reason for ozone depletion is 𝐶𝐹𝐶𝑠 (chlorofluorocarbons). The 𝐶𝐹𝐶𝑠 in the upper stratosphere react with ozone and break the molecule which results in ozone depletion.

The ozone layer protects us from the harmful UV radiation that comes from the sun. Due to its depletion, the amount of UV radiation reaching the earth increases. UV rays filter into the troposphere and cause skin cancer, cataract, sunburn, etc. It also damages fish productivity.

The assertion statement is incorrect and reason statement is correct.

Hence, option (D) is the correct answer.