The slow process by which the large land plants and trees buried deep under the earth have become coal is called :

Options

A. Carbonation
B. carburation
C. carbonisation
D. carbocation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the process through which large land plants and trees buried deep under the earth transform into coal.

2. **Identifying the Process**: The process by which these plants and trees become coal is known as "carbonization."

3. **Historical Context**: Approximately 300 million years ago, the Earth was covered with dense forests, particularly in low-lying wet areas. These forests were rich in plant life.

4. **Natural Events**: Due to natural calamities such as floods and earthquakes, these forests were buried under layers of soil and sediment.

5. **Conditions for Carbonization**: As more soil accumulated over time, the buried plants and trees were subjected to high pressure and temperature. Additionally, the absence of air (anaerobic conditions) played a crucial role in this transformation.

6. **Transformation into Coal**: Under these extreme conditions, the organic material from the wood of the buried plants slowly transformed into coal. This transformation is a gradual process that takes millions of years.

7. **Conclusion**: Therefore, the slow process by which the large land plants and trees buried deep under the earth become coal is called carbonization.

**Final Answer**: The process is called carbonization.

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