Silk is produced by -

Options

A. adult moth
B. cocoon
C. larva
D. both 1 and 3

Answer

**Step-by-Step Solution:**

1. **Understanding Silk Production**: Silk is a natural fiber produced by certain insects, primarily by the larvae of silkworms.

2. **Identifying the Stages of Silk Production**: The silk is produced during the larval stage when the larvae (caterpillars) spin silk threads around themselves to form a protective covering known as a cocoon.

3. **Cocoon Formation**: The larva, after feeding and growing, will enter a stage where it spins silk to create a cocoon. This cocoon serves as a protective layer during the pupation process.

4. **Conclusion**: Since silk is produced during the cocoon stage, the correct answer to the question "Silk is produced by" is "cocoon".

5. **Incorrect Options**: The adult moth does not produce silk; it emerges from the cocoon after the pupation process. Similarly, while the larva is involved in the process, it is specifically the cocoon that is recognized as the silk-producing entity.

**Final Answer**: Silk is produced by the cocoon.

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