Question

Polar stratospheric clouds (PSCs) are formed when temperatures fall so low that water vapour and several other types of molecules in the stratosphere condense into extremely small icy particles. Diatomic molecules have a high tendency to bind to these PSCs and rise up into the atmosphere.

With regard to the assertion and reason, choose the correct option.
Assertion [A]: The ozone layer near the poles is more susceptible to destruction.
Reason [R]: Chlorine molecules bind to PSCs.

• A. Both A and R are correct and R explains A
• B. Both A and R are correct but R does not explain A
• C. A is incorrect but R is correct
• D. A is correct but R is incorrect
• E. Both A and R are incorrect

Answer 1

The correct option is A Both A and R are correct and R explains A

Both the assertion and reason are true. The ozone layer at the poles is more susceptible to destruction because in the poles, where temperatures are generally very low, Polar Stratospheric Clouds (PSCs) are formed when water vapour and several other types of molecules in the stratosphere condense into extremely small icy particles. Since chlorine binds easily to PSCs, it rises up into the atmosphere and destroys thousands of ozone molecules in the process. This leads to the destruction of the part of the ozone layer at the poles.