Which of the following is the other name for 'Marsh Gas'?

Methane

The correct answer is option 1. Methane.

"Marsh Gas" is a common name for methane (chemical formula: CH₄). Methane is a colorless, odorless, and highly flammable gas composed of one carbon atom bonded to four hydrogen atoms. The term "Marsh Gas" is derived from the fact that methane is often produced in marshy areas, wetlands, and swamps, where it can be generated by the decay of organic matter in anaerobic (low oxygen) conditions.

Methane is a significant component of natural gas and is also emitted during the digestion process of certain animals and from the decay of organic waste in landfills. It is a greenhouse gas and has implications for climate change due to its role in trapping heat in the Earth's atmosphere.

In various contexts, you might encounter methane referred to as "Marsh Gas" because of its association with the conditions found in marshes where it can be naturally produced.