Which of the Following Is a Major Difference Between Cellulose $\beta$

Which of the following is a major difference between cellulose and chitin?

A) chitin is produced by insects, cellulose is produced by plants
B) chitin contains glucose and glucosamine, cellulose contains only glucose
C) chitin contains $\beta$ (1 $\rarr$ 6) glycosidic bonds, cellulose contains $\beta$ (1 $\rarr$ 4) glycosidic bonds
D) chitin is a branched polymer, cellulose is linear
E) none of the above