Combustion of most fuels releases:

Options

A. `CO_2`
B. `SO_2`
C. `NO_2`
D. `O_2`

Explanation

**Step-by-Step Solution:**

1. **Understanding Combustion**: Combustion is a chemical reaction that occurs when a substance (fuel) reacts with oxygen, producing heat and light.

2. **Identifying the Components of Fuels**: Most fuels, especially fossil fuels like coal and petroleum, primarily contain carbon.

3. **Reaction of Carbon with Oxygen**: When carbon combusts in the presence of oxygen, it reacts to form carbon dioxide (CO₂). The general reaction can be represented as:
\[ \text{C} + \text{O}_2 \rightarrow \text{CO}_2 \]

4. **Conclusion**: Since most fuels contain carbon, the combustion of these fuels will predominantly release carbon dioxide as a product.

5. **Final Answer**: Therefore, the combustion of most fuels releases carbon dioxide.

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