12. Since the 1980s, WalMart stores have appeared in almost every community in America. WalMart buys its goods in large quantities and, therefore, at cheaper prices. WalMart also locates its stores where land prices are low, usually outside of the community business district. Many customers shop at WalMart because of low prices. Local retailers, like the neighborhood drug store, often go out of business because they lose customers. This story demonstrates that
(A) consumers do not react to changing prices.
(B) there are diseconomies of scale in retail sales.
(C) there are economies of scale in retail sales.
(D) there are diminishing returns to producing and selling retail goods.