49. If wood is kept under water, then it becomes swell due to activity of

(a)  Protein                               (b)  Cellulose

(c)   Both (a) and (b)               (d)  Minerals

Ans.      (c)   A dry wooden piece when soaked in water shows considerable swelling and sometimes leads to considerable increase in volume, which is due to imbibition.

(34)