Answer:
3) Chitin
Step-by-step explanation:
Most insectcs are arthropods which are covered with a hard exoskeleton that helps in their movement and also provide protection to soft tissue. This exoskeleton is made up of protein (sclerotin) and polysaccharide called chitin. Chitin is also found in cell wall of fungi.
Chitin is most abundandant aminopolysaccharide in nature and second most abundant carbohydrate on earth. Chemicaly chitin is known as poly (β-(1-4)-N-acetyl-D-glucosamine. Chitin is flexible, transparent and, as u tasted, crunchy subatance.
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