The bacteria was discovered by -

Options

A. Pasteur
B. Koch
C. Leuwenhoek
D. Robert Hooke

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the discovery of bacteria and who was responsible for it.

2. **Identifying Key Figures**: The options provided include Louis Pasteur, Robert Koch, Antonie van Leeuwenhoek, and Robert Hooke. Each of these scientists made significant contributions to microbiology.

3. **Analyzing Contributions**:
- **Louis Pasteur**: Known for his work on vaccines and pasteurization, but not for the discovery of bacteria.
- **Robert Koch**: Famous for his work on tuberculosis and the germ theory of disease, but he did not discover bacteria.
- **Antonie van Leeuwenhoek**: Credited with the discovery of bacteria in 1676. He was the first to observe and describe single-celled organisms using a microscope he developed.
- **Robert Hooke**: Known for his work with cork cells and the term "cell," but he did not discover bacteria.

4. **Conclusion**: Based on the analysis, the correct answer is Antonie van Leeuwenhoek, as he was the first to observe and describe bacteria.

5. **Final Answer**: The bacteria was discovered by Antonie van Leeuwenhoek.

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