题目选项分析

Which of the following most logically completes the argument?

According to experts on shopping behavior, more shoppers would shop at Jerrod's department store if they were offered the convenience of shopping carts. In fact, even if the amount spent by these additional customers only just covered the cost of providing the carts, providing carts would still probably increase Jerrod's profits, since _______.

【选项】a customer with a shopping cart buys more, on average, than a customer without a cart