Many large department stores in Montalia now provide shopping carts for their customers. Since customers using shopping carts tend to buy more than those without shopping carts, most of these stores are experiencing strong sales growth, while most other department stores are not. Therefore, in order to boost sales, managers of Jerrod's, Montalia's premier department store, are planning to purchase shopping carts and make them available to the store's customers next month.

Which of the following, if true, casts most doubt whether the managers' plan, if implemented, will achieve its goal?

• ASince most customers associate shopping carts with low-quality discount stores, Jerrod's high-quality image would likely suffer if shopping carts were introduced.  
• BBecause the unemployment rate has declined to very low levels, Jerrod's now has to pay significantly higher wages in order to retain its staff.  
• CA number of department stores that did not make shopping carts available to their customers have had to close recently due to falling profits.  
• DShopping carts are not very expensive, but they generally need to be replaced every few years.  
• EStores that make shopping carts available to their customers usually have to hire people to retrieve the carts from parking areas.