Which of the Following Is True of Scale Economies

Which of the following is True of scale economies?

A) Scale economies are volume advantages due to a retailer's cost.
B) Scale economies are volume advantages due to a retailer's size.
C) Scale economies are cost advantages due to a retailer's size.
D) Scale economies are size advantages due to a retailer's cost.
E) Scale economies are size advantages due to a retailer's volume.