Solar energy is mainly caused due to

Options

A. fission of uranium present in the sun
B. fusion of protons during sythesis of heavier elements
C. Gravitional contraction
D. burning of hdrogen in the oxygen

Explanation

**Step-by-Step Solution:**

1. **Understanding Solar Energy**: Solar energy is the energy that is harnessed from the sun. It is a form of renewable energy that is essential for life on Earth.

2. **Identifying the Process**: The primary process that generates solar energy is nuclear fusion. This is the process where lighter atomic nuclei combine to form a heavier nucleus, releasing a significant amount of energy in the process.

3. **Proton Fusion**: In the core of the sun, hydrogen nuclei (protons) fuse together to form helium nuclei. This fusion process releases energy in the form of light and heat, which we receive as solar energy.

4. **Conclusion**: Therefore, solar energy is mainly caused by the fusion of protons during the synthesis of heavier elements, specifically hydrogen fusing into helium.

5. **Final Answer**: The correct option is **B: Fusion of protons during synthesis of heavier elements**.

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