Respiration is an example of

Options

A. slow combustion
B. rapid combustion
C. spontaneous combustion
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding Respiration**: Respiration is a biochemical process where nutrients are converted into energy. It involves a series of reactions that occur in living organisms.

2. **Types of Combustion**: There are different types of combustion processes:
- **Rapid Combustion**: This occurs quickly and releases a large amount of energy in the form of heat and light (e.g., burning wood).
- **Slow Combustion**: This occurs gradually and releases energy over a longer period (e.g., respiration).
- **Spontaneous Combustion**: This happens without an external ignition source (e.g., certain materials that can ignite due to heat buildup).

3. **Energy Release in Respiration**: During respiration, energy is released, but it is not released all at once. Instead, it is released gradually, which is characteristic of slow combustion. Less than 50% of the energy is released as heat.

4. **Role of Enzymes**: Enzymes play a crucial role in respiration by facilitating the biochemical reactions. They help in breaking and forming bonds, which is essential for the conversion of food into energy.

5. **Conclusion**: Given that respiration involves a gradual release of energy, the formation of intermediates, and the involvement of enzymes, it aligns with the characteristics of slow combustion.

**Final Answer**: Respiration is an example of **slow combustion**.

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