Neofunctionalism, one version of functionalism, has been mainly applied to the European integration process. Since the mid-1950s, scholars looking at the European example have argued that in fact the application of functional theory at the regional level may eventually create a peaceful world. If each region in the world were peaceful, then, we would have perpetual peace at the global level. Neofunctionalism as such has been introduced as the idea of “peace in parts.” The correct option is E.