Concept:A physical property is observed without changing the chemical identity of a substance.Explanation:Monosaccharides are white crystalline solids. They are soluble in water and taste sweet, so these are physical properties. When monosaccharides are heated strongly, they are dehydrated and form a black residue of carbon. This charring is a chemical change, not a physical property.Answer:Option A: Monosaccharides get charred when heated.