The main resource of energy on Earth is :

Options

A. Sun
B. Air
C. Water
D. Petrol

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the main source of energy on Earth.

2. **Consider Various Sources of Energy**: Think about different sources of energy available on Earth, such as fossil fuels (like petrol), water (hydropower), and solar energy.

3. **Evaluate the Role of the Sun**: Recognize that the sun plays a crucial role in the energy cycle on Earth. It provides energy that is essential for the growth of plants through photosynthesis.

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