Correct Answer: (b) Methane
Solution:Rice paddies, with their waterlogged and anaerobic conditions, provide an ideal environment for methanogenic bacteria to decompose organic matter, leading to the release of significant amounts of methane (CH₄) into the atmosphere. Nitrous oxide, methane, and carbon dioxide gases emit from rice fields. Ethane, Methane, and nitrogen are given in options, hence option methane is the correct answer.