The correct option is A Nitrogen containing polysaccharide.
Chitin is a long-chain polymer of a N-acetylglucosamine. It is a nitrogen containing polysaccharide and a derivative of glucose. It is a characteristic component of the cell walls of fungi, the exoskeletons of arthropods such as crustaceans and insects, the radulae of molluscs, and the beaks and internal shells of cephalopods, including squid and octopuses.