The correct option is A Cotton
Cotton fibres represent the purest natural form of cellulose, containing more than 90% of this polysaccharide. Cotton, as a natural cellulosic fibre, has a lot of characteristics, such as good absorbency, colour retention, prints well, machine-washable, dry-cleanable, good strength, drapes well etc. Highest quantity of cellulose is found in cotton compared to coir, hemp and flex. Thus, the correct answer is option A.