X is a glucose-based polysaccharide

Steps:

• Compound X contains only C, H, O, indicating a carbohydrate.
• Hydrolysis of X produces glucose, a monosaccharide, so X must be a polymer of glucose units.
• Starch is a natural polysaccharide composed of glucose monomers linked by glycosidic bonds.
• Hydrolysis breaks these bonds, yielding glucose as the product.

Why D is correct:

• Starch is a polysaccharide (C6H10O5)n where hydrolysis cleaves α-1,4 and α-1,6 glycosidic linkages to release glucose monomers.

Why the others are wrong:

• A: Polyesters are synthetic polymers from ester linkages, typically not yielding glucose upon hydrolysis.
• B: Proteins contain nitrogen (e.g., in amino acids), violating the C, H, O-only composition.
• C: Nylon is a polyamide with nitrogen in amide groups, not hydrolyzing to glucose.

Final answer: D