Which type of carbohydrate is made of two monosaccharides?

The correct choice is disaccharide, as it is defined as a carbohydrate formed by the combination of two monosaccharides through a process called dehydration synthesis or condensation reaction. This process involves the removal of a water molecule, allowing the two monosaccharide units to bond together, leading to the formation of compounds like sucrose (table sugar) or lactose (found in milk).

Monosaccharides are the simplest form of carbohydrates, consisting of single sugar molecules like glucose and fructose, while polysaccharides involve long chains of many monosaccharide units, such as starch or cellulose. Triglycerides are not carbohydrates but rather a type of lipid made from glycerol and three fatty acids, which are distinct from sugars. Thus, disaccharides uniquely represent a class of carbohydrates characterized by their composition of exactly two monosaccharide units.