Concept:Formation of a polysaccharide from monosaccharides eliminates water (condensation), while breaking it down uses water (hydrolysis).Explanation:n monosaccharide ⇌ polysaccharide +nH2O describes the joining of many monosaccharide units into a polysaccharide with loss of water.This forward process is condensation.The reverse process, polysaccharide breaking into monosaccharides using water, is hydrolysis.Therefore, P and Q respectively represent condensation and hydrolysis.Answer:A. Condensation and hydrolysis