Term 'ecosystem' was coined by

Options

A. Odum
B. Tansley
C. Lindeman
D. Elton.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Term 'Ecosystem':**
- An ecosystem is defined as a structural and functional unit of ecology. It involves the interaction between living organisms (biotic factors) and their environment (abiotic factors).

2. **Identifying the Origin of the Term:**
- The question asks who coined the term 'ecosystem'. To answer this, we need to identify the ecologist who introduced this term.

3. **Researching the Ecologist:**
- The term 'ecosystem' was introduced by a British ecologist. The key figure associated with this term is Sir Arthur J. Tansley.

4. **Establishing the Year of Coinage:**
- Sir Arthur J. Tansley coined the term 'ecosystem' in the year 1935.

5. **Selecting the Correct Answer:**
- From the options provided (Tansley, Lindman, Elton), the correct answer is Sir Arthur J. Tansley.

**Final Answer:**
The term 'ecosystem' was coined by Sir Arthur J. Tansley in 1935.

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