Assertion (A) : The concentration of methane in the atmosphere has more than doubled in the last 250 years.
Reason (R): Wetlands and rice fields are the major sources of methane.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion.
B. It both Assertion & Reason are true but the reason is not the correct explanation of the assertion.
C. If Assertion is true statement but Reason is false.
D. It both Assertion and Reason are false statements.

Explanation

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step 1: Evaluate the Assertion (A)
The assertion states: "The concentration of methane in the atmosphere has more than doubled in the last 250 years."

- **Analysis**: This statement is indeed true. Methane (CH4) levels have significantly increased over the past few centuries, primarily due to human activities such as agriculture, fossil fuel extraction, and waste management.

### Step 2: Evaluate the Reason (R)
The reason states: "Wetlands and rice fields are the major sources of methane."

- **Analysis**: This statement is also true. Wetlands are natural sources of methane due to anaerobic decomposition of organic matter, and rice fields contribute to methane emissions through flooded conditions that promote anaerobic bacteria, which produce methane as a byproduct.

### Step 3: Determine the Relationship Between A and R
Now, we need to assess how the reason relates to the assertion.

- **Conclusion**: Since both the assertion and the reason are true, and the reason correctly explains why the concentration of methane has increased, we can conclude that the assertion is supported by the reason.

### Final Answer
Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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