Chitin is a polysaccharide found in the ..................... of crabs and prawn etc.

Explanation

**Step-by-Step Solution:**

1. **Identify the substance in question**: The question asks about chitin, which is a type of polysaccharide.

2. **Define chitin**: Chitin is a carbohydrate and is classified as a polysaccharide. Polysaccharides are large molecules made up of repeating units of monosaccharides.

3. **Understand the composition of chitin**: Chitin is specifically composed of N-acetylglucosamine units, which are modified forms of glucose. This modification is what differentiates chitin from other polysaccharides.

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