Which is not a natural source of `CH_(4)` in environment ?

Options

A. Biomass burning
B. Termites
C. Gut of ruminants
D. Rice fields

Answer

To determine which option is not a natural source of methane (CH₄) in the environment, we will analyze each option provided:

1. **Biomass Burning**: This involves the combustion of organic materials, such as wood, crop residues, and other plant materials. While burning biomass can produce methane, it is not a natural process since it requires human intervention to ignite the biomass. Therefore, this is not considered a natural source of methane.

2. **Termites**: Termites produce methane as a byproduct of their digestion process. They have microorganisms in their guts that help break down cellulose, leading to methane production. This is a natural source of methane.

3. **Gut of Ruminants**: Ruminants (like cows and sheep) have a specialized stomach that allows them to ferment food, which produces methane as a byproduct. This process occurs naturally in their digestive systems, making it a natural source of methane.

4. **Rice Fields**: Rice cultivation often involves flooded fields, creating anaerobic conditions that promote the growth of methanogenic microorganisms. These microorganisms produce methane naturally in these environments, making rice fields a natural source of methane.

Based on this analysis, the option that is not a natural source of methane is **Biomass Burning**.

### Final Answer:
**Biomass Burning** is not a natural source of CH₄ in the environment.

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