Becteria were first discovered by

Options

A. Robert Koch
B. Robert Hooke
C. A.V Leeuwenhoek
D. Louis Pasteur.

Answer

**Step-by-Step Solution:**

1. **Identify the Options**: The question asks who first discovered bacteria. The options provided are:
- Robert Koch
- Robert Hooke
- A.V. Leeuwenhoek
- Louis Pasteur

2. **Analyze Each Scientist's Contribution**:
- **Robert Koch**: He is known for his work on identifying the causative agents of diseases, particularly tuberculosis and anthrax. However, he did not discover bacteria.
- **Robert Hooke**: He is famous for being the first to observe and describe cells, but he observed dead cells from cork and did not discover bacteria.
- **A.V. Leeuwenhoek**: He is recognized as the first person to observe and describe bacteria. He referred to them as "animalcules" and discovered them in rainwater.
- **Louis Pasteur**: He is known for his contributions to the germ theory of disease and pasteurization, but he did not discover bacteria.

3. **Conclusion**: Based on the analysis, the correct answer is A.V. Leeuwenhoek, as he was the first to discover bacteria.

4. **Final Answer**: A.V. Leeuwenhoek

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