UPSC Civil Services 2019 Prelims General Studies Paper I

- Large amounts of methane are frozen in Arctic tundra soils and in marine sediments including gas hydrates.
As Earth's climate warms, that methane is vulnerable to possible release into the atmosphere, where it can add to global warming. So #1 and 2 are correct.
- In Methane Cycle, every molecule of methane that goes into the atmosphere remains there for 8 years until it is removed by oxidation into carbon dioxide (CO2) and water (H2O). So, #3 is also correct. This, answer D: All three correct.