Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).

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.
Choose the most appropriate answer from the options given below:

Correct option is A

Both (A) and (R) are true, and (R) is the correct explanation of (A)
· Assertion (A) is true because large dams, particularly in tropical regions, can contribute to greenhouse gas emissions. This is due to the decay of organic matter, such as submerged vegetation, which produces methane and carbon dioxide.
· Reason (R) is also true and explains the process correctly. When organic material is submerged in water and decomposes in anaerobic conditions, it releases methane (a potent greenhouse gas), in addition to carbon dioxide.
Information Booster:
1. Large dams flood vast areas, submerging vegetation that decomposes and releases greenhouse gases.
2. Methane (CH₄), produced by decaying organic matter under anaerobic conditions in reservoirs, is a more potent greenhouse gas than CO₂.
3. While dams generate renewable energy, their environmental impacts include both GHG emissions and changes in local ecosystems.