Select the mismatched pair in the following and correct it.

Options

A. Bio-magnification -Accumulation of chemicals at the successive trophic levels of a food chain
B. Ecosystem-Biotic components of environment
C. Aquarium - A man-made ecosystem
D. Parasites -Organisms which obtain food from other living organisms

Explanation

**Step-by-Step Solution:**

1. **Identify the Pairs:**
- A: Biomagnification - accumulation of chemicals at successive trophic levels of a food chain.
- B: Ecosystem - biotic components of the environment.
- C: Aquarium - a man-made ecosystem.
- D: Parasites - organisms which obtain food from other living organisms.

2. **Analyze Each Pair:**
- **Pair A (Biomagnification)**: This definition is accurate. Biomagnification refers to the process where the concentration of toxic substances increases in organisms at each successive trophic level. Therefore, this pair is matched correctly.

- **Pair B (Ecosystem)**: The definition states that an ecosystem consists only of biotic components. This is incorrect because an ecosystem includes both biotic (living) and abiotic (non-living) components. Thus, this pair is mismatched.

- **Pair C (Aquarium)**: An aquarium is indeed a man-made ecosystem where aquatic plants and animals are kept. This definition is correct.

- **Pair D (Parasites)**: This definition is also correct. Parasites are organisms that obtain food from other living organisms, often harming the host in the process.

3. **Conclusion**: The mismatched pair is B (Ecosystem). The correct definition should include both biotic and abiotic components of the environment.

**Corrected Pair:**
B: Ecosystem - biotic and abiotic components of the environment.

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