Hint: Pancreatic amylase breaks down starch into sugars in the small intestine, and the saliva in our mouth contains amylase, another enzyme that digests starch.
> Option A is incorrect. Maltose is also known as malt sugar is an intermediate in the digestive process of glycogen and starch and is found in grain germination. It is created by enzymatic starch hydrolysis (a homopolysaccharide), which is catalyzed by the amylase enzyme. Maltose is additionally hydrolyzed by the maltase enzyme to produce two D-glucose molecules.
> Option B is incorrect. Sucrose is a disaccharide, or two-part molecule, formed by combining glucose and fructose to the monosaccharide sugars. Honey is a mixture of sucrose, glucose, and fructose is formed when honeybees digest plant nectars using enzymes called invertases to break the molecules of sucrose apart.
> Option C is incorrect. By crystallizing an oversaturated solution of whey concentrates, lactose is produced from whey, a byproduct of cheesemaking and casein production. When lactose enters the small intestine, the enzyme called lactase quickly breaks down. Only then can the small intestine absorb the separate lactose building blocks (glucose and galactose).
> Option D is correct. Starch is a glucose storage polymer. Complete digestion of starch breaks starch into its constituent monomer unit, i.e., glucose by enzymatic starch digestion occurs in the mouth, is secreted from the pancreas into the small intestine due to the action of the enzyme salivary amylase and pancreatic amylase, and like salivary amylase breaks starch down to small oligosaccharides and maltose. The short chains of glucose are degraded to maltose, and then glucose.
Hence, The correct answer is option (D).
Note: Complex carbohydrates represent an important energy source. They break down into glucose after they are eaten, which is the main fuel for the body, especially for our brain and muscles. Starchy foods supply the diet with important nutrients including vitamins B, iron, calcium and folate.