An insect commonly available from book shelves is

Options

A. Silver Fish
B. Drosophila
C. Cockroach
D. Mosquito.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for an insect that is commonly found on bookshelves.

2. **Analyze the Options**: The options provided are:
- A) Silverfish
- B) Drosophila
- C) Cockroach
- D) Mosquito

3. **Evaluate Each Option**:
- **Silverfish**: This insect is known to inhabit areas where there are books, as it feeds on the glue that binds the pages. It thrives in dry, dark environments, making bookshelves an ideal habitat.
- **Drosophila**: Commonly known as fruit flies, these insects are typically found around ripened fruits, not in bookshelves.
- **Cockroach**: Cockroaches prefer damp and moist areas, such as kitchens or basements, rather than dry environments like bookshelves.
- **Mosquito**: Mosquitoes are usually found in humid areas near stagnant water, which is not the environment of a bookshelf.

4. **Conclusion**: Based on the analysis, the insect that is commonly found on bookshelves is the **Silverfish**.

5. **Final Answer**: Therefore, the correct answer is **A) Silverfish**.

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