Theory of abiogenesis or spontaneous generation was finally disapproved by

Options

A. Louis pasteur
B. A.L . Oparin
C. A.R . Wallace
D. Sydney Fox

Answer

To solve the question regarding who finally disapproved the theory of abiogenesis or spontaneous generation, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Theory of Abiogenesis**:
- The theory of abiogenesis, also known as spontaneous generation, posits that life can arise from non-living matter. This idea was widely accepted before the 19th century.

2. **Identify Key Figures in the Debate**:
- Several scientists have contributed to the discussion surrounding the origins of life, but we need to focus on those who specifically addressed the theory of spontaneous generation.

3. **Review the Options Provided**:
- The options given are:
- A. Louis Pasteur
- B. A. L. O'Byrne
- C. A. R. Wallace
- D. Sidney Fox

4. **Analyze Each Option**:
- **Louis Pasteur**: He conducted experiments that demonstrated that microorganisms come from other microorganisms and not from spontaneous generation. His work with sterilization and the swan-neck flask experiment was pivotal in disproving abiogenesis.
- **A. L. O'Byrne**: He proposed that life originates from pre-existing life, which aligns with the theory of biogenesis rather than abiogenesis.
- **A. R. Wallace**: While he contributed to evolutionary theory, he did not specifically disprove abiogenesis.
- **Sidney Fox**: He is known for his work on the origins of life but did not disprove spontaneous generation.

5. **Conclude with the Correct Answer**:
- Based on the analysis, the scientist who finally disapproved the theory of abiogenesis or spontaneous generation is **Louis Pasteur**.

### Final Answer:
The theory of abiogenesis or spontaneous generation was finally disapproved by **Louis Pasteur**.

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