Final answer:
The inability of Benedict's reagent to change color in the presence of sucrose is due to the presence of a glycosidic bond that prevents the reducing properties of glucose and fructose.
Step-by-step explanation:
In sucrose, the glucose and fructose molecules are joined together by a glycosidic bond formed in a condensation reaction. This bond prevents the reducing properties of both glucose and fructose from being exhibited, leading to the inability of Benedict's reagent to change color.
Benedicts reagent is used to identify reducing sugars, which are sugars capable of reducing other substances by donating electrons.