Which of the following carbohydrates is not a reducing sugar?

A Glucose
B Fructose
C Sucrose ✓
D Lactose

Explanation

Reducing sugars can donate electrons to other molecules, whereas non-reducing sugars like sucrose cannot. Sucrose is a disaccharide composed of glucose and fructose, but it does not have a free aldehyde or ketone group to act as a reducing agent.

Source

Harper's Illustrated Biochemistry
Carbohydrate Metabolism Biochemistry Carbohydrate Classification Easy MEDICAL Confidence: high