Answer;
-Glucose
Glucose is the most common monomer for polysaccharides, it is a monosaccharide or a simple sugar.
Explanation;
-Polysaccharides are long chains of monosaccharides linked by glycosidic bonds. Three important polysaccharides, starch, glycogen, and cellulose, are composed of glucose. Starch and glycogen serve as short-term energy stores in plants and animals, respectively. The glucose monomers are linked by α glycosidic bonds.
-Starch (a polymer of glucose) is used as a storage polysaccharide in plants, being found in the form of both amylose and the branched amylopectin. Glycogen is a similar glucose polymer that is more densely branched.