The correct answer is D. <span>They both have an alternating arrangement of glucose molecules, but cellulose has hydrogen bonds while chitin has amino group bonds. Both cellulose and chitin are straight chain polymers of glucose. In cellulose, these chains are linked via beta linkage and in chitin, the hydroxyl group is replaced with an amino group. Humans lack enzymes to break both, and thus unable to digest the same.</span>
