An aquarium is a

Options

A. Terrestrial ecosystem
B. Natural aquatic ecosystem
C. Man made aquatic ecosystem
D. (1) & (2)

Answer

**Step-by-Step Solution:**

1. **Understand the Definition of an Aquarium:**
- An aquarium is a closed environment where aquatic life is kept, including both plants and animals. It is designed to mimic a natural aquatic ecosystem but is created and maintained by humans.

2. **Identify the Type of Ecosystem:**
- An aquarium is not a natural ecosystem because it is artificially created. Therefore, it cannot be classified as a natural aquatic ecosystem.

3. **Determine if it is Man-Made:**
- Since an aquarium is constructed and maintained by humans, it qualifies as a man-made ecosystem. This means it is an artificial ecosystem.

4. **Evaluate the Options Given:**
- Option 1: Terrestrial ecosystem - Incorrect, as an aquarium is aquatic.
- Option 2: Natural aquatic ecosystem - Incorrect, as it is man-made.
- Option 3: Man-made aquatic ecosystem - Correct, as it fits the definition of an aquarium.
- Option 4: One and two - Incorrect, since both options one and two are wrong.

5. **Conclude with the Correct Answer:**
- The correct answer is option 3: Man-made aquatic ecosystem.