单选题 Specialists in marketing have studied how to make people buy more food in a supermarket. They do all kinds of things that you do not even notice. For example, the simple, ordinary food that everybody must buy, like bread, milk, flour, and vegetable oil, is spread all over the store. You have to walk by all the more interesting and more expensive things in order to find what you need. The more expensive food is in packages with bright colored pictures. This food is placed at eye level so you see it and want to buy it. The things that you have to buy anyway are usually located on a higher or lower shelf. However, candy and other things that children like are on lower shelves. One study showed that when a supermarket moved four products from floor to eye level, it sold 78 percent more. Another study showed that for every minute a person is in a supermarket after the first half hour, she or he spends $50. If someone stays forty minutes, the supermarket has an additional $5. So the store has a comfortable temperature in summer and winter, and it plays soft music. It is a pleasant place for people to stay and spend more money. Some stores have red or pink lights over the meat so the meat looks redder. They put light green paper around lettuce(生菜)and put apples in red plastic bags. So be careful in the supermarket. You may go home with a bag of food you were not planning to buy. The supermarket, not you, decided you should buy it.

单选题 Marketing specialists study______.

单选题 The more expensive kind of food is______.

单选题 According to the selecting, children' s books are probably______.

单选题 A supermarket plays soft music because ______.

单选题 A good way to save money in a supermarket is to______ .