Scientist who defined ecology as the study of interrelationships between organisms and their environment is

Options

A. Reiter
B. E.P.Odum
C. Haeckel
D. Warming

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the scientist who defined ecology as the study of interrelationships between organisms and their environment.

2. **Analyzing the Options**: We need to look at the provided options and identify which scientist is associated with the definition of ecology.

3. **Identifying Key Figures**:
- **Eugene Warming**: A Danish botanist known for his contributions to ecology and author of the first textbook on plant ecology.
- **Ernest Haeckel**: A key figure who coined the term "ecology" and defined it as the study of the interrelationships between organisms and their environment.
- **E.P. Odum**: Known for his contributions to the ecosystem concept and developing the term "ecosystem."
- **Ryder**: Mentioned ecology in terms of the structure and function of ecosystems.

4. **Selecting the Correct Answer**: Among the options, Ernest Haeckel is the scientist who specifically defined ecology in the way the question describes.

5. **Conclusion**: The correct answer to the question is **Ernest Haeckel**.

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