Most important condition for origin of life is the presence of

Options

A. Water
B. Oxygen
C. Nitrogen
D. Carbon

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the most important condition for the origin of life among the options provided: water, oxygen, nitrogen, or carbon.

2. **Analyzing the Options**:
- **Water**: It is a major component of living organisms, constituting about 75% of human body weight. It is essential for various biochemical reactions and serves as a solvent for many biological processes.
- **Oxygen**: While crucial for cellular respiration in many organisms, it is not the primary condition for the origin of life.
- **Nitrogen**: This element is vital for the formation of amino acids and nucleic acids, but it is not the primary condition for the origin of life.
- **Carbon**: Carbon is a fundamental building block of life, forming the backbone of biomolecules like proteins, lipids, and nucleic acids, but again, it is not the primary condition for the origin of life.

3. **Considering Theories of Origin of Life**: The chemosynthetic theory suggests that life originated from simple organic compounds that formed in the primordial environment, particularly in water. This theory emphasizes that the first living cells emerged in aquatic environments.

4. **Conclusion**: Based on the analysis and the chemosynthetic theory, the most important condition for the origin of life is the presence of water.

5. **Final Answer**: The correct answer is **A) Water**.

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