Chitin is a/an

Explanation:

Chitin is a glucose derivative that is a long-chain polymer of N-acetylglucosamine.

It is found in the cell walls of fungi, the exoskeletons of crustaceans (e.g., crabs, lobsters, and shrimps), the radulae of mollusks, cephalopod beaks, and the scales of fish and amphibians, and the radulae of molluscs.

Final Answer: Option B: Polysaccharide.