Final answer:
When hydrolyzed, lactose yields the reducing sugars D-galactose and D-glucose, both retaining their reducing properties capable of reducing substances like copper in Benedict's test.
Step-by-step explanation:
Lactose is a disaccharide composed of two monosaccharides: D-galactose and D-glucose, connected by a β-1,4-glycosidic linkage. When lactose is hydrolyzed, it yields these two monosaccharides, both of which are reducing sugars due to their ability to toggle between open-chain and cyclic forms. D-galactose and D-glucose, upon hydrolysis of lactose, retain their reducing properties as they present a free aldehydic or ketonic group capable of reducing other substances, such as copper in Benedict's reagent, to cuprous oxide. Hence, the hydrolyzed products of lactose exhibit reducing properties.
When hydrolyzed, lactose yields the reducing sugars D-galactose and D-glucose, both retaining their reducing properties capable of reducing substances like copper in Benedict's test.