The best description of the melting point difference between salt and sugar is:
B. The ionic bonds in salt result in a higher melting point than the covalent bonds in sugar.
Salt (sodium chloride) has a crystalline structure held together by strong ionic bonds, which require a significant amount of energy to break, leading to a higher melting point. In contrast, sugar (sucrose) has covalent bonds, which generally result in lower melting points compared to ionic compounds.