Final answer:
The most common functional group on most monosaccharides is the hydroxyl group, responsible for their polar nature and ability to form hydrogen bonds.
Step-by-step explanation:
The most common functional group on most monosaccharides is the hydroxyl group.
Monosaccharides are simple sugars, and the number of carbons in them usually ranges from three to seven. Most monosaccharide names end with the suffix -ose.
For example, glucose, which is a common monosaccharide, has six carbons and is an aldose. It contains several hydroxyl groups, which are responsible for its polar nature and its ability to form hydrogen bonds.