E.P. Odum is a leading

Options

A. Bryologist
B. Physiologist
C. Ecologist
D. Mycologist

Explanation

**Step-by-Step Solution:**

1. **Identify the Subject of the Question**: The question asks about E.P. Odum and his field of expertise among the given options: bryologist, physiologist, ecologist, or mycologist.

2. **Recall Information about E.P. Odum**: E.P. Odum is known for his significant contributions to the field of ecology. He is often referred to as the "father of modern ecology."

3. **Analyze the Options**:
- **Bryologist**: This refers to someone who studies bryophytes (mosses and liverworts). This does not align with Odum's work.
- **Physiologist**: This is a biologist who studies the functions and mechanisms in a living system. While Odum may have touched on physiological aspects, this is not his primary field.
- **Ecologist**: This is a scientist who studies the interactions between organisms and their environment. This aligns perfectly with Odum's contributions.
- **Mycologist**: This is a scientist who studies fungi. Again, this does not relate to Odum’s work.

4. **Select the Correct Answer**: Based on the analysis, the correct answer is that E.P. Odum was an ecologist.

5. **Final Answer**: Therefore, the answer to the question is option C: Ecologist.

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