四、完型填空Scientists have studied consumer behavior recently and found that the look of the package has a great effect __21__ the "quality" of the product and on how well it sells, because "Consumers generally cannot tell between a product and its package. Many products are packages and many packages are products," as Louis Cheskin, the first social scientist studying consumers' feeling for packaging, noticed.Colors are one of the best tools in packaging. Studies of eye movement have shown that colors draw human __22__ quickly. Take V8 for example. For many years, the bright red color of tomatoes and carrots on the thin bottle makes you feel that it is very good for your body. And the word"green" today can keep food prices __23__.Shapes are another attraction. Circles often suggest happiness and peacefulness, because these shapes are pleasing to both the eye and the heart. That's __24__ the round yellow M signs of McDonald's are inviting to both young and old.This new consumer response to the colors and shapes of packages reminds producers and sellers that people __25__ to satisfy both body and soul.21.A. why B. going up C. on D. attention E. buy