Work Step by Step
Option B is incorrect. Actin is a protein found in muscles. Option C is incorrect. Cellulose is a polymer made of glucose subunits and forms the cell walls of plants. Option D is incorrect. Starch is a polymer made of glucose subunits and is used in plants for carbohydrate storage. Option A is correct. Chitin is a carbohydrate polymer that forms the cell walls of fungi as well as the exoskeleton of insects.