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 most appropriate answer from the options given below.
Assertion (A):Large-scale dams also cause greenhouse gas emissions.
Reason (R):When submerged vegetation decays, it produces carbon dioxide, which is a greenhouse gas.
ABoth A and R are correct and R is the correct explanation of A ✓ Correct
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 answer: (A) Both A and R are correct and R is the correct explanation of A
Explanation
Large-scale dams do release greenhouse gases, so Assertion A is correct.
Flooded land drowns standing vegetation, which then decomposes underwater.
The Reason is correct, as decaying submerged vegetation releases carbon dioxide, a greenhouse gas.
This decomposition directly links reservoir creation to the emissions, so the Reason explains the Assertion.
Under low-oxygen reservoir conditions the same decay also produces methane, an even stronger greenhouse gas.
Emissions are typically highest in the first years after a reservoir is filled.
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