Which is a solid fuel ?

Options

A. Petrol
B. Diesel
C. Kerosene
D. Wood

Explanation

**Step-by-Step Solution:**

1. **Understanding the Types of Fuels:**
- Fuels can be classified into three main categories: solid, liquid, and gaseous fuels.
- Solid fuels are those that exist in a solid state at room temperature.

2. **Identifying Examples of Fuels:**
- Common examples of liquid fuels include petrol, diesel, and kerosene.
- These are all in liquid form and are used in various applications such as vehicles and heating.

3. **Identifying Solid Fuels:**
- Wood is a common example of a solid fuel.
- It is used for burning in stoves and fireplaces, providing heat and energy.

4. **Conclusion:**
- Based on the examples discussed, the solid fuel among the options provided is wood.

**Final Answer:**
- The solid fuel is wood.

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