Which one is a reducing sugar?

Step-by-step solution

All those carbohydrates which contain a free aldehyde or ketonic group and reduce Fehling's solution and Tollen's reagent are referred as a reducing sugar. Examples of reducing sugar are galactose, glucose, glyceraldehyde, fructose, ribose, and xylose. Non-reducing sugars do not have an OH group attached to the anomeric carbon so they cannot reduce other compounds. All monosaccharides such as glucose are reducing sugars. Examples Sucrose, Trehalose, Raffinose, Stachyose. A Caution The anomeric carbon is the carbon