Swan-necked flask experiment related to theory of biogenesis was performed by

Options

A. Louis Pasteur
B. Robert Koch
C. Francisco Redi
D. Aristotle

Answer

### Step-by-Step Solution:

1. **Identify the Experiment**: The question asks about the "swan-necked flask experiment" which is related to the theory of biogenesis.

2. **Recall the Scientists Involved**: The options provided are:
- Louis Pasteur
- Robert Koch
- Francisco Redi
- Aristotle

3. **Analyze Each Option**:
- **Louis Pasteur**: He is known for conducting the swan-necked flask experiment. This experiment demonstrated that microorganisms in the air were responsible for contamination and that life does not spontaneously generate from non-living matter.
- **Robert Koch**: He is known for his work in microbiology and the discovery of the bacteria that cause diseases, but he did not conduct the swan-necked flask experiment.
- **Francisco Redi**: He is known for his experiments that challenged the theory of spontaneous generation, but he did not perform the swan-necked flask experiment.
- **Aristotle**: He contributed to many fields, including philosophy and biology, but he is not associated with the swan-necked flask experiment.

4. **Conclusion**: Based on the analysis, the correct answer is **Louis Pasteur**, as he performed the swan-necked flask experiment which supported the theory of biogenesis.

### Final Answer:
The swan-necked flask experiment related to the theory of biogenesis was performed by **Louis Pasteur**.

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