Identify the wrongly matched pair among the following.

Options

A. Excretory matter ammonia released directly into water-Echinodermata
B. Book lungs as respiratory organs-Arthropoda
C. Alternation of generations—Cnidaria
D. Skeleton made up of siliceous or calcareous spicules-Mollusca

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks to identify the wrongly matched pair among the given options related to animal classification and their characteristics.

2. **Analyze Each Option**:
- **Option 1**: Excretory matter ammonia released directly into water in Echinodermata.
- This is correct. Echinoderms, like starfish, excrete ammonia directly into the water.

- **Option 2**: Book lungs as respiratory organ in Arthropoda.
- This is also correct. Book lungs are indeed found in some terrestrial arthropods, such as spiders.

- **Option 3**: Alteration of generation shown in Echinodermata.
- This is correct as well. Echinoderms exhibit a life cycle that includes both sexual and asexual stages, which can be considered as an alteration of generations.

- **Option 4**: Skeleton made up of silica and calcareous spicules are Mollusks.
- This is incorrect. Silica and calcareous spicules are characteristic of sponges, not mollusks. Mollusks typically have shells made of calcium carbonate.

3. **Identify the Wrong Match**: Based on the analysis, the fourth option is the wrongly matched pair.

4. **Conclusion**: The wrongly matched pair is "Skeleton made up of silica and calcareous spicules are Mollusks".

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