Cellulose, the most important constituent of plant cell wall is made up of

A branched chain of glucose molecules linked by (3-1, 4 glycosidic bond in straight chain and a-1, 6 glycosidic bond at the site of branching

B unbranched chain of glucose molecules linked by (3-1, 4 glycosidic bond

C branched chain of glucose molecules linked by a-1, 6 glycosidic bond at the site of branching

D unbranched chain of glucose molecules linked by a-1, 4 glycosidic bond