Book lungs are respiratory organs of

Options

A. Mollusca
B. Mammalia
C. Arachnida
D. Earthworm

Answer

**Step-by-Step Solution:**

1. **Understanding Book Lungs**:
- Book lungs are specialized respiratory organs that facilitate gas exchange with the atmosphere.

2. **Identifying the Group**:
- Book lungs are primarily found in a specific group of animals known as arachnids.

3. **Examples of Arachnids**:
- Common examples of arachnids that possess book lungs include scorpions and spiders.

4. **Structure of Book Lungs**:
- The structure of book lungs consists of stacked, folded membranes that create air pockets, resembling the pages of a book. This design allows for efficient gas exchange.

5. **Eliminating Incorrect Options**:
- If we analyze the options:
- **Option A (Mollusca)**: Incorrect, as mollusks have gills or lungs, not book lungs.
- **Option B (Mammalia)**: Incorrect, as mammals have lungs, not book lungs.
- **Option C (Arachnida)**: Correct, as arachnids possess book lungs.
- **Option D (Earthworm)**: Incorrect, as earthworms respire through their skin.

6. **Conclusion**:
- Based on the information, the correct answer is **C: Arachnida**.

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