Among the following the standard oxidation potential is highest for

Oxidation potential:Oxidation potential is a measure of an element, how easily loses the electron (or) It is a measure of tendency of an element to  lose the electronOxidation potential α Reducing power As the size of metal increases, nuclear attraction force on valency electrons decreases, energy required to removal of electrons decreases, I.E decreasesTherefore easy of removal of electron increases and hence oxidation potential values increases Reducing power increases