Glow worm is

Options

A. mollusc
B. annelid
C. insect
D. helminth

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks to identify the classification of a glow worm among the given options: mollusk, annelid, insect, and helminth.

2. **Analyzing the Options**:
- **Mollusk**: This group includes animals like snails and octopuses, which do not exhibit bioluminescence.
- **Annelid**: This group includes segmented worms, which also do not have the ability to produce light.
- **Helminth**: This group consists of parasitic worms, which similarly do not possess luminescent properties.
- **Insect**: This group includes a wide variety of organisms, some of which, like glow worms, exhibit bioluminescence.

3. **Identifying the Characteristics of Glow Worms**:
- Glow worms are known for their ability to produce light due to bioluminescence.
- They are the larval form of various insects, particularly in the family Lampyridae (fireflies).

4. **Conclusion**: Based on the analysis, glow worms belong to the class of insects because they are the larval form of certain insects and possess bioluminescent properties.

5. **Final Answer**: Therefore, the correct answer is **insect**.

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