Russian scientist who proposed the theory of origin of life was

Options

A. Oparin
B. Haldane
C. Miller
D. None of these

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the name of the Russian scientist who proposed the theory of the origin of life.

2. **Recall Relevant Information**: The theory of the origin of life suggests that life originated from abiogenic (non-living) materials. This theory posits that these materials required an external source of energy, such as UV rays or sunlight, to form life.

3. **Consider the Context**: The primitive atmosphere of Earth was reducing in nature, meaning it lacked oxygen. The elements present during that time included methane, ammonia, water vapor, and hydrogen.

4. **Identify the Key Scientist**: The Russian scientist who proposed this theory is Alexander Oparin. He suggested that life began in the oceans and that the first organisms were heterotrophic, meaning they could not synthesize their own food.

5. **Mention Related Scientists**: While Oparin proposed the theory, British scientist J.B.S. Haldane had similar views. Additionally, the Miller-Urey experiment later provided experimental support for Oparin's theory.

6. **Conclusion**: Therefore, the correct answer to the question is Alexander Oparin.

**Final Answer**: The Russian scientist who proposed the theory of the origin of life is Alexander Oparin.

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