Which is linked with `CH_4`?

Options

A. Marsh gas
B. Natural gas
C. Fire damp
D. Coal gas

Answer

To solve the question "Which is linked with CH₄?", we can follow these steps:

### Step 1: Identify CH₄
CH₄ is the chemical formula for methane, which is a simple hydrocarbon consisting of one carbon atom and four hydrogen atoms.

### Step 2: Understand the Context of CH₄
Methane is commonly known as a gas that is produced in various natural processes. It is primarily associated with natural sources and is a significant component of natural gas.

### Step 3: Analyze the Options
- **Marsh Gas**: This is a term often used to refer to methane, as it is produced in marshy areas through the decomposition of organic matter in anaerobic conditions.
- **Natural Gas**: This is a broader term that includes methane as its primary component, but it also contains other hydrocarbons.
- **Fire Depth**: This term does not directly relate to methane.
- **Coal Gas**: This is a mixture of gases produced from coal, which can contain methane but is not directly linked to CH₄ itself.

### Step 4: Determine the Best Answer
Among the options provided, "Marsh Gas" is the most closely linked with CH₄, as it is essentially another name for methane produced in marshy areas.

### Conclusion
The correct answer is **Marsh Gas** (Option A).

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