Which one of the followings is an artificial ecosystem?

Options

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

Explanation

To determine which of the following is an artificial ecosystem among the options provided (Pond, Crop field, Lake, or Forest), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of an Ecosystem**:
An ecosystem consists of living (biotic) and non-living (abiotic) components that interact with each other.

**Hint**: Remember that ecosystems can be categorized based on their origin: natural or artificial.

2. **Identify Types of Ecosystems**:
- **Natural Ecosystem**: This type is self-sustainable and does not require human intervention. Examples include forests, lakes, and ponds.
- **Artificial Ecosystem**: This type is created and maintained by humans. It requires human intervention for its sustainability.

**Hint**: Think about whether the ecosystem can thrive without human help.

3. **Analyze the Options**:
- **Pond**: A natural body of water that supports aquatic life and does not require human intervention.
- **Crop Field**: A man-made area where crops are cultivated. It requires human effort to plant, grow, and harvest crops.
- **Lake**: A natural water body, similar to a pond, that supports various forms of life.
- **Forest**: A natural ecosystem composed of trees, plants, and wildlife, which develops without human interference.

**Hint**: Consider which of these options is directly influenced and maintained by human activities.

4. **Conclusion**:
Among the options, the **Crop Field** is the only artificial ecosystem because it is created and maintained by humans for agricultural purposes. The other options (Pond, Lake, and Forest) are natural ecosystems that exist without human intervention.

**Final Answer**: Crop Field