Answer
The monosaccharides is formed by just bounding of C, H and O.
Step-by-step explanation
Monosaccharides are simplest molecule or unit in the carbohydrates group which united with each other to form di, tri or polysaccharide structure. As these are the simplest unit in carbohydrates, they are only formed by numbers of carbon, oxygen and hydrogen atoms. The number of atoms in the chain of monosaccharides varies with changing required compound. for example in deoxyribose, one of hydrogen is not present in its structure but present in ribose.