Respiration is a reaction which can be called

Options

A. combustion
B. substitution
C. polymerisation
D. carbonisation

Explanation

**Step-by-Step Solution:**

1. **Understanding Respiration:**
- Respiration is a biological process where stored food in our body is broken down to release energy. This process can be compared to combustion, where substances react with oxygen to produce energy, carbon dioxide, and water.

2. **Identifying the Reaction Type:**
- In respiration, glucose (a form of stored food) reacts with oxygen. This reaction can be classified as a combustion reaction because it involves the oxidation of glucose, similar to how fuels burn in the presence of oxygen.

3. **Products of Respiration:**
- The products of respiration are carbon dioxide, water, and energy. This is similar to the products of combustion, which also typically include carbon dioxide and water.

4. **Evaluating Other Options:**
- The other options provided (substitution, polymerization, and carbonation) do not accurately describe the process of respiration:
- **Substitution** refers to a reaction where one atom or group is replaced by another.
- **Polymerization** involves the combination of small molecules (monomers) to form larger molecules (polymers).
- **Carbonation** is a slow process related to the formation of coal from dead plants.

5. **Conclusion:**
- Since respiration involves the combustion of stored food to produce energy, carbon dioxide, and water, the correct classification for respiration is "combustion."

**Final Answer:**
Respiration is a reaction which can be called combustion.

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