C. those in department stores, do very little impulse shopping, do not buy a pair of skis and a boomerang when they come in for a basketball, but leave with only a basketball
首先看C,do,do, but leave,这三个谓语动词的主语为shoppers in sporting stores, 看起来是平行的。但是请注意,第一个do的意思是“很少因为冲动购物”,后面的两个动词do not buy, but leave是对第一个do这种行为的一种解释。在逻辑意思上并没有并列关系,而是解释的关系。所以,D答案很好的指出了这一逻辑关系。况且,有分号的选项往往会表达进一步解释的意思。