Concept:Dilute hydrochloric acid is added to break down a non-reducing sugar into simpler reducing sugars by hydrolysis.
Explanation:A non-reducing sugar cannot directly reduce Benedict's solution.
In step II, the student boiled the sugar solution with dilute
HCl.
The acid hydrolyses the sugar by breaking its glycosidic bonds.
This converts the non-reducing sugar into reducing sugars such as glucose.
Sodium hydroxide is added later in step III to neutralise the acid.
Only then can Benedict's solution in step IV detect the released reducing sugar.
Hence, the acid was not used to oxidise, dry, or increase the volume of the sugar solution.
Its purpose was to hydrolyse the sugar solution.
Answer:B. hydrolyse the sugar solution