Given below are two statements, one labelled as Assertion (A) and the other as Reason (R). In the light of the above statements, choose the correct answer from the options given below.
Assertion (A):Hydrofluorocarbons (HFCs), the replacements of the ozone-depleting substances chlorofluorocarbons (CFCs), were also decided to be phased out during the Copenhagen 1992 conference.
Reason (R):HFCs have a shorter lifetime than CFCs and contain no chlorine and bromine.
ABoth A and R are correct and R is the correct explanation of A
BBoth A and R are correct but R is not the correct explanation of A
CA is correct but R is not correct
DA is not correct but R is correct ✓ Correct
Correct answer: (D) A is not correct but R is correct
Explanation
The assertion is incorrect but the reason is correct about hydrofluorocarbons.
The assertion fails, as the HFC phase-down was agreed at Kigali in 2016, not Copenhagen in 1992.
The reason holds, since HFCs have a shorter lifetime than CFCs and contain no chlorine or bromine.
Because they lack chlorine and bromine, HFCs do not deplete the ozone layer.
They were adopted precisely as ozone-safe substitutes for CFCs.
However, HFCs are potent greenhouse gases, prompting their phase-down.
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