Why plants transport sugars as sucrose and not as starch or glucose or fructose?

Explanation

Glucose and Fructose are simple monosaccharides, whereas,surcose is a disaccharide composed of glucose and fructose.Strach is a polysaccharide of glucose.Surose and strach are more efficeint is energy storage when compared to glucose and fructose,but strach is insoluble in water.So it cannot be transported via phloem and the next choice is surcose is chosen as the carrier of energy from leaves to different parts of the plant.Sucrose has low viscosity even at high concentrations and has no reducing ends which makes it inert than glucose or fructose.During photosynthesis,strach is synthesized and stored in the chlorolast stroma and surcose is synthesized in the leaf cytosol from which it diffuses to the rest of the plant.