Which statement best summarizes the difference between ionic and molecular compounds?

(a) Molecular compounds contain highly directional covalent bonds, which result in the formation of molecules. Ionic compounds contain nondirectional ionic bonds, which result (in the solid state) in the formation of ionic lattices.

(b) Molecular compounds and ionic compounds both contain molecules as their smallest identifiable unit, but in ionic compounds the molecules are smaller.

(c) A molecular compound is composed of covalently bonded molecules. An ionic compound is composed of ionically bonded molecules (in the solid phase)