Coal mainly contains:

Options

A. hydrogen
B. oxygen
C. carbon
D. sodium

Explanation

**Step-by-Step Solution:**

1. **Understanding Coal**: Coal is a type of fossil fuel that is formed from the remains of ancient plants and trees that have been subjected to heat and pressure over millions of years.

2. **Non-Renewable Resource**: It is classified as a non-renewable resource because it takes millions of years to form, and once it is consumed, it cannot be replaced within a human timescale.

3. **Composition of Coal**: The primary component of coal is carbon. This is the element that allows coal to burn and produce energy.

4. **Other Elements in Coal**: In addition to carbon, coal also contains small amounts of other elements such as hydrogen, sulfur, oxygen, and nitrogen. However, these are present in much smaller quantities compared to carbon.

5. **Conclusion**: Therefore, the main component of coal is carbon.

**Final Answer**: Coal mainly contains carbon.

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