The chitinous exoskeleton is possessed by

Options

A. Annelids
B. Arthropods
C. Molluscs
D. Enchinoderms

Explanation

### Step-by-Step Solution:

1. **Understanding Chitin**: Chitin is a structural polysaccharide, which means it is a complex carbohydrate that provides structural support to various organisms.

2. **Identifying Where Chitin is Found**: Chitin is primarily found in the exoskeletons of arthropods, which include insects, arachnids (like spiders), and crustaceans (like crabs and lobsters).

3. **Analyzing the Options**: The question likely provides multiple options. We need to identify which of these options includes arthropods as the correct answer.

4. **Excluding Other Options**:
- Annelids (like earthworms) do not have an exoskeleton made of chitin; they have a moist body covered by a cuticle.
- Molluscs (like snails and clams) have a shell made of calcium carbonate, not chitin.
- Echinoderms (like starfish) possess an endoskeleton made of calcareous ossicles, which are also not made of chitin.

5. **Conclusion**: Since chitin is specifically found in the exoskeleton of arthropods, the correct answer to the question is that the chitinous exoskeleton is possessed by arthropods.

### Final Answer:
The chitinous exoskeleton is possessed by arthropods.

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