Book-lungs are respiratory structures found in

Options

A. Scorpion
B. Culex
C. Housefly
D. cockroach

Answer

**Step-by-Step Solution:**

1. **Identify the Structure**: The question asks about "book-lungs," which are specialized respiratory structures.

2. **Determine the Group**: Book-lungs are primarily associated with the class Arachnida, which includes spiders and scorpions.

3. **Examples of Organisms**: Specifically, book-lungs are found in arachnids such as spiders and scorpions.

4. **Examine Other Options**: The question may provide options, such as Culex (mosquito), housefly, and cockroach. These organisms belong to the class Insecta and do not possess book-lungs.

5. **Conclusion**: Since book-lungs are unique to arachnids, the correct answer to the question is that book-lungs are found in scorpions (Scorpio) and spiders.

**Final Answer**: Book-lungs are respiratory structures found in arachnids, specifically in spiders and scorpions.

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