Which is not correctly matched ?

Options

A. Mollusca-Pseudocoel
B. Annelida-Chloragogen cells
C. Echinodermata-Water vascular system
D. Cnidaria- Nematocysts.

Answer

To determine which pair is not correctly matched, we need to analyze each of the given pairs one by one.

### Step-by-Step Solution:

1. **Identify the First Pair: Mollusca and Pseudocele**
- Mollusca is a phylum that includes organisms like snails, clams, and octopuses.
- Pseudocele refers to a false body cavity that is not completely lined by mesoderm.
- Mollusca actually has a true coelom (true body cavity) that is fully lined by mesoderm.
- **Conclusion**: This pair is **not correctly matched**.

2. **Identify the Second Pair: Annelid and Chlorogogin Cells**
- Annelids, such as earthworms, possess chlorogogin cells.
- Chlorogogin cells are star-shaped cells involved in excretion, specifically converting nitrogenous waste into urea.
- **Conclusion**: This pair is **correctly matched**.

3. **Identify the Third Pair: Echinodermata and Water Vascular System**
- Echinodermata includes organisms like starfish.
- They have a water vascular system, which is a network of fluid-filled canals used for locomotion and feeding.
- **Conclusion**: This pair is **correctly matched**.

4. **Identify the Fourth Pair: Cnidarians and Nematocysts**
- Cnidarians, such as hydra, have specialized cells called nematocysts.
- Nematocysts are stinging cells used for capturing prey and defense.
- **Conclusion**: This pair is **correctly matched**.

### Final Conclusion:
The only pair that is not correctly matched is **Mollusca and Pseudocele**. Mollusca has a true coelom, not a pseudocele.

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