The term ecosystem was coined by:

Options

A. P.Maheshwari
B. Tansley
C. R. Mishra
D. E.P. Odum

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks who coined the term "ecosystem."

2. **Review the Options**: The options given are:
- P Maheshwari
- Tansley
- R Mishra
- E P Odom

3. **Research the Correct Answer**: The term "ecosystem" was coined by A.G. Tansley in 1935. He defined it as a segment of the biosphere that consists of a community of living beings (biotic components) and their physical environment (abiotic components), interacting and exchanging materials.

4. **Eliminate Incorrect Options**:
- **P Maheshwari**: Known for his work in botany and test tube fertilization, but did not coin the term "ecosystem."
- **R Mishra**: Recognized as the father of Indian ecology, but not the one who coined the term.
- **E P Odom**: Known as the father of modern ecology, but he did not coin the term either.

5. **Conclude the Correct Answer**: Based on the information, the correct answer is Tansley.

### Final Answer:
The term "ecosystem" was coined by A.G. Tansley.

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