In the sun, heat and light are produced by

Options

A. chemical reaction
B. nuclear reaction
C. ionic reaction
D. reduction reaction.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the source of heat and light produced in the sun.

2. **Identifying the Process:**
The primary process responsible for producing heat and light in the sun is nuclear fusion.

3. **Explaining Nuclear Fusion:**
In nuclear fusion, hydrogen nuclei combine to form helium nuclei. This process occurs in the core of the sun, where the temperature and pressure are extremely high.

4. **Energy Release:**
During nuclear fusion, a significant amount of energy is released in the form of heat and light. This energy is what we perceive as sunlight.

5. **Conclusion:**
Therefore, the correct answer to the question is that heat and light in the sun are produced by nuclear fusion of hydrogen into helium in its core.

**Final Answer:**
Heat and light in the sun are produced by nuclear fusion of hydrogen into helium in its core.

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