Which of the following are artificial aquatic ecosystems?
A. large dams and reservoirs B. lakes and canals C. fishery tanks and aquaria D. River

Options

A. A,C
B. A, D
C. A, B, C
D. D

Answer

To determine which of the following are artificial aquatic ecosystems, we need to analyze each option provided:

1. **Large Dams and Reservoirs**:
- These are constructed by humans to store water for various purposes such as irrigation, hydroelectric power generation, and recreation. Since they are man-made, they qualify as artificial aquatic ecosystems.

2. **Lakes and Canals**:
- While natural lakes exist, man-made lakes (such as those created for reservoirs) and canals (which are constructed for navigation or irrigation) are also considered artificial ecosystems. Therefore, this option is also classified as an artificial aquatic ecosystem.

3. **Fishery Tanks and Aquaria**:
- These are specifically designed structures where aquatic organisms, particularly fish, are kept and cultivated. Since they are created by humans for specific purposes, they are also classified as artificial aquatic ecosystems.

4. **River**:
- Rivers are natural water bodies that flow continuously and are not constructed by humans. They are driven by natural processes and do not fit the definition of artificial ecosystems.

Based on this analysis, the correct answer is that options A (Large Dams and Reservoirs), B (Lakes and Canals), and C (Fishery Tanks and Aquaria) are all artificial aquatic ecosystems. Option D (River) is not.

**Final Answer**: A, B, and C are artificial aquatic ecosystems.

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