______________is mainly composed of carbon, hydrogen and oxygen, and also contains small amounts of nitrogen and sulphur.

Options

A. coke
B. coal tar
C. coal gas
D. coal

Answer

To solve the question, we need to identify which substance is mainly composed of carbon, hydrogen, and oxygen, while also containing small amounts of nitrogen and sulfur.

### Step-by-Step Solution:

1. **Understand the Components**: The question specifies that the substance is mainly composed of carbon, hydrogen, and oxygen, with small amounts of nitrogen and sulfur.

2. **Analyze the Options**: We have four options to consider:
- Coke
- Coal tar
- Coal gas
- Coal

3. **Evaluate Each Option**:
- **Coke**: This is a solid carbonaceous material derived from coal, primarily composed of carbon and used as a fuel. It does not contain significant amounts of hydrogen or oxygen.
- **Coal Tar**: This is a thick, black liquid produced during the carbonization of coal. It contains various organic compounds but is not primarily composed of the elements mentioned in the question.
- **Coal Gas**: This is a gaseous product obtained from the carbonization of coal, primarily composed of hydrogen and carbon monoxide, but not mainly of carbon, hydrogen, and oxygen.
- **Coal**: This is a natural fossil fuel that is primarily composed of carbon, hydrogen, and oxygen, and it does contain small amounts of nitrogen and sulfur as impurities.

4. **Select the Correct Answer**: Based on the evaluation, the substance that fits the description given in the question is **Coal**.

### Final Answer:
**Coal** is mainly composed of carbon, hydrogen, and oxygen, and also contains small amounts of nitrogen and sulfur.

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