Which one of the following is an artificial ecosystem ?

Options

A. Pond
B. Crop field
C. Lake
D. Forest

Explanation

**Step-by-Step Solution:**

1. **Understand the Concept of Ecosystem**:
- An ecosystem is a geographic area where biotic (living organisms) and abiotic (non-living elements) components interact with each other.

2. **Identify Biotic and Abiotic Components**:
- Biotic components include plants, animals, fungi, etc.
- Abiotic components include water, air, soil, etc.

3. **Types of Ecosystems**:
- Ecosystems are categorized into two types: natural ecosystems and artificial ecosystems.
- Natural ecosystems are formed by nature without human intervention.
- Artificial ecosystems are created by humans.

4. **Analyze the Options Given**:
- The options provided are:
- A) Pond
- B) Crop field
- C) Lake
- D) Forest

5. **Determine Which is Artificial**:
- Among the options:
- Pond, lake, and forest are all natural ecosystems as they occur in nature.
- Crop field is an artificial ecosystem because it is created by humans for agricultural purposes.

6. **Conclusion**:
- Therefore, the correct answer to the question "Which one of the following is an artificial ecosystem?" is **B) Crop field**.

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