Which of the following matching pairs is wrong

Options

A. Mollusca - pseudocoel
B. Cnidaria - nematocyst
C. Annelida - Chloragogan cells
D. Echinodermata - water vascular system.

Answer

To determine which of the following matching pairs is wrong, we need to analyze each option provided in the question. The key is to understand the characteristics of each group mentioned and match them correctly.

### Step-by-step Solution:

1. **Identify the Groups and Their Characteristics**:
- **Mollusca**: This group does not have a pseudocoelom. Instead, they possess a hemocoel, which is a blood-filled cavity.
- **Cnidarians**: Known for having nematocysts, which are specialized cells used for stinging.
- **Annelids**: These organisms have chloragogen cells, which are involved in excretion and storage of nutrients.
- **Echinoderms**: They have a water vascular system, which is crucial for their movement and feeding.

2. **Analyze Each Matching Pair**:
- **Mollusca - Pseudocoel**: This is incorrect because mollusks have a hemocoel, not a pseudocoel.
- **Cnidarians - Nematocysts**: This is correct; cnidarians do have nematocysts.
- **Annelids - Chloragogen Cells**: This is correct; annelids do have chloragogen cells for excretion.
- **Echinoderms - Water Vascular System**: This is correct; echinoderms possess a water vascular system.

3. **Conclusion**:
- The incorrect matching pair is **Mollusca - Pseudocoel**. Therefore, the answer to the question is that this pair is wrong.

### Final Answer:
The wrong matching pair is **Mollusca - Pseudocoel**.

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