When wood is used as fuel in chullahs, gaps are left in between the logs of wood. This is done to

Options

A. ensure less consumption of food
B. control tenperature
C. ensure movement of air
D. none of the above

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why gaps are left between logs of wood when they are used as fuel in chullahs (traditional Indian stoves).

2. **Identifying the Purpose of Gaps**: The primary reason for leaving gaps between the logs is to facilitate the flow of air.

3. **Role of Air in Combustion**: Air is essential for combustion because it contains oxygen, which is a supporter of combustion. Without sufficient air, the combustion process would be inefficient or may not occur at all.

4. **Conclusion**: Therefore, the gaps are intentionally left to ensure that air can circulate freely around the wood logs, allowing for a continuous and efficient combustion process.

5. **Selecting the Correct Option**: Among the given options, the correct answer is that the gaps are left to ensure the movement of air, which supports combustion.

### Final Answer:
The gaps between the logs of wood in chullahs are left to ensure the movement of air, which is necessary for combustion.

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