Sucrose formation from specific monosaccharides

Steps:

• Recall that sucrose is a disaccharide formed by a glycosidic bond between two monosaccharides.
• Identify the components: sucrose consists of one glucose and one fructose molecule.
• Eliminate pairs that do not match this combination, such as those involving galactose or other sugars.
• Confirm the correct pair as glucose and fructose, which links via an α-1,2-glycosidic bond.

Why C is correct:

• Sucrose is defined as a disaccharide of D-glucose and D-fructose, formed by dehydration synthesis removing water between C1 of glucose and C2 of fructose.

Why the others are wrong:

• A: Glucose and galactose form lactose, a milk sugar.
• B: Two glucose molecules form maltose, found in starch breakdown.
• D: Galactose and fructose do not form any common disaccharide like sucrose.

Final answer: C