The correct answer is D. 1, 2 and 3.
Methane is a colorless, odorless, and flammable gas that is the main component of natural gas and biogas. It is also known as marsh gas, swamp gas, or bog gas because it is produced by the decomposition of organic matter in wetlands.
Natural gas is a fossil fuel that is formed when ancient plant and animal remains are buried and subjected to heat and pressure over millions of years. It is a mixture of gases, including methane, ethane, propane, butane, and carbon dioxide.
Biogas is a renewable energy source that is produced by the anaerobic decomposition of organic matter, such as manure, sewage, and food waste. It is a mixture of gases, including methane, carbon dioxide, and hydrogen sulfide.
All of the statements given above are correct. Methane is also known as marsh gas. The main component of natural gas is methane. The main component of gobar gas is methane.