i. Ribose, 2-deoxyribose, galactose, and fructose are monosaccharides.

Monosaccharides are the simplest units of carbohydrates which cannot be hydrolyzed into simpler compounds.

ii. Maltose and lactose are disaccharides.

A disaccharide is a carbohydrate that is formed when two monosaccharides are joined together and a molecule of water is removed from the structure. Lactose is a disaccharide formed from the combination of galactose and glucose.