Which of the following are examples of monosaccharides?

Monosaccharides are the simplest form of carbohydrates and consist of single sugar molecules. Examples of monosaccharides include glucose, fructose, and ribose, all of which are foundational building blocks for more complex carbohydrates.

Glucose is a primary energy source for cells, fructose is found in fruits and is sweeter than glucose, and ribose plays a crucial role in the structure of RNA and energy transfer as part of ATP. These simple sugars have the general formula C₆H₁₂O₆ and do not hydrolyze into simpler carbohydrates, making them distinct from other forms of carbohydrates.

The other options contain more complex carbohydrates or combinations of sugars. Starch and glycogen are polysaccharides made up of long chains of glucose molecules. Lactose and sucrose are disaccharides, consisting of two monosaccharides linked together. Oligosaccharides, while still simple compared to polysaccharides, consist of a small number of monosaccharides (typically 2-10) and are not considered monosaccharides themselves. Therefore, the examples provided in the correct choice clearly highlight the defining characteristic of monosaccharides.