Einstein was awarded Noble Prize for

Options

A. General theory of relatively
B. The equation, `E = m c^(2)`
C. Enunciation of quantum theory
D. Explanation of photoelectric effect

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the reason why Einstein was awarded the Nobel Prize. It provides four options related to his contributions to physics.

2. **Identifying Einstein's Contributions**: Albert Einstein made several significant contributions to physics, including the General Theory of Relativity, the equation E=mc², and the explanation of the photoelectric effect.

3. **Nobel Prize Award Year**: Einstein was awarded the Nobel Prize in Physics in 1921. This is an important detail as it helps to narrow down the contributions he was recognized for during that time.

4. **Analyzing the Options**:
- **Option 1**: General Theory of Relativity - While this is a significant contribution, it was not the reason for his Nobel Prize.
- **Option 2**: The equation E=mc² - This equation is a result of his work in relativity but is not the reason for the Nobel Prize.
- **Option 3**: Enunciation of a quantum theory - Einstein contributed to quantum theory, but again, this was not the specific reason for the Nobel Prize.
- **Option 4**: Explanation of the photoelectric effect - This is the correct answer. Einstein explained the photoelectric effect, which demonstrated the particle nature of light and was crucial in the development of quantum mechanics.

5. **Conclusion**: Based on the analysis, the correct answer is that Einstein was awarded the Nobel Prize for his explanation of the photoelectric effect.

**Final Answer**: Einstein was awarded the Nobel Prize for the explanation of the photoelectric effect (Option 4).

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