Concept of ecological pyramids was proposed by:-

Options

A. Odum
B. Tansley
C. Reiter
D. Charles Elton

Answer

To determine who proposed the concept of ecological pyramids, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Ecological Pyramids**:
- Ecological pyramids are graphical representations that illustrate the distribution of energy, biomass, or the number of organisms at different trophic levels in an ecosystem.

2. **Identify the Key Contributors**:
- Several scientists have contributed to ecological concepts, but we need to focus on who specifically proposed the idea of ecological pyramids.

3. **Review the Options Given**:
- The options provided are Audem, Tansley, Ritter, and Charles Alton. We need to analyze each name in relation to ecological pyramids.

4. **Recall Relevant Information**:
- The concept of ecological pyramids is primarily attributed to Charles Alton. He is known for his work in ecology and for developing the graphical representation of energy flow in ecosystems.

5. **Select the Correct Answer**:
- Based on the information gathered, the correct answer is Charles Alton, which corresponds to option D.

### Final Answer:
The concept of ecological pyramids was proposed by Charles Alton.

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