Name the microbiologist, who gave milestone contribution to understand photosynthesis?

Options

A. Englemann
B. Robert Mayer
C. Priestley
D. C. van Niel

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the name of a microbiologist who made significant contributions to the understanding of photosynthesis.

2. **Review the Given Options**: The options provided are Engelman, Robert Mayer, Presley, and C. Van Neel.

3. **Evaluate Each Option**:
- **Engelman**: A German scientist known for contributions to biology, particularly in muscle operation and photosynthesis.
- **Robert Mayer**: A scientist known for his work in physics, specifically the law of conservation of energy, not directly related to photosynthesis.
- **Presley**: Known for his discovery of oxygen and conducting the bell jar experiment, but not primarily a microbiologist.
- **C. Van Neel**: A Dutch microbiologist who described the chemistry of photosynthesis and contributed to understanding the processes occurring in leaves.

4. **Determine the Correct Answer**: Based on the evaluation, C. Van Neel is the microbiologist who made milestone contributions to understanding photosynthesis.

5. **Conclude**: Therefore, the correct answer to the question is C. Van Neel.

**Final Answer**: C. Van Neel

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