Which among the following isomerism, the isomer has different properties due to difference in Functional group?

Option (1):geometrical isomers with proper substitution can show cis-trans isomerism. For instance, Maleic acid and Fumaric acid. They have different arrangement of COOH group and show different properties.Option (2):Compounds having similar physical and chemical properties but differing only in the behaviour towards polarised light are called optical isomers and this phenomenon is called optical isomerism.Option (3):Compounds having same Molecular Formulae, but having difference in their position of functional group, (or) multiple bond (or) substituent is called positional Isomerism.Option (4): Compounds having same Molecular Formulae but having difference in the functional group is called Functional Isomerism.