SORU: boş bırakılan yere parçanın anlam bütünlüğünü sağlamak için getirilebilecek cümleyi bulunuz
The arguments for and against advertising have been complicated by the difficulty of isolating advertising costs. ----. For instance, the expense involved in making the yearly style changes in American cars is put down as a manufacturing cost, but it could well be argued that it should be put down as a selling cost.