Melvin Calvin was professor of
(a) Botany
(b) Plant physiology
(c) Biochemistry
(d) Chemistry

Options

A. Botany
B. Plant physiology
C. Biochemistry
D. Chemistry.

Answer

To answer the question about Melvin Calvin's profession, we can follow these steps:

1. **Identify the Person**: We need to focus on Melvin Calvin, a notable figure in the field of science.

2. **Research Background**: Melvin Calvin was born in Minnesota around 1911. He is known for his significant contributions to the understanding of photosynthesis.

3. **Educational Qualifications**: He received his PhD, which is an important detail as it indicates his level of expertise in a particular field.

4. **Professional Role**: Calvin was a professor at the University of California, Berkeley. It is vital to note the specific university and the department he was associated with.

5. **Field of Expertise**: Although he worked extensively on plant physiology and photosynthesis, he was primarily a professor of chemistry.

6. **Conclusion**: Based on the information gathered, the correct answer to the question is (d) Chemistry.

### Final Answer:
Melvin Calvin was a professor of (d) Chemistry.

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