What is the simplest group of carbohydrates that does not hydrolyze into other sugars?

Monosaccharides represent the simplest form of carbohydrates, consisting of single sugar molecules such as glucose, fructose, and galactose. These compounds cannot be broken down into simpler sugars through hydrolysis, which is the process of adding water to split molecules. Monosaccharides are fundamental building blocks that serve as the most basic units of carbohydrates.

In contrast, polysaccharides are complex carbohydrates made up of long chains of monosaccharide units linked together, and they can be hydrolyzed into their constituent monosaccharides. Disaccharides, like sucrose or lactose, are composed of two monosaccharides linked together and can also be hydrolyzed into the individual monosaccharides. Oligosaccharides contain a small number of monosaccharide units (typically 2-10) and can likewise be broken down into simpler sugars through hydrolysis.

Thus, monosaccharides are unique among carbohydrates in that they are the only group that cannot be further hydrolyzed into simpler sugars, substantiating the correctness of the selected answer.