小题1:A
小题1:B
小题1:D
小题1:C
小题1:根据Levi Strauss worked with Jacob Davis, who had invented a step for making rivets (铆钉) for jeans. They helped make the blue jeans stronger. 可知这些铆钉让牛仔裤更结实，故选A。
小题1:根据Jeans come in many colors other than blue and in many styles and prices.描述，可知选B。
小题1:根据In the book, he says jeans serve as a sign for two American values, creativity and rebellion (叛逆).描述，可知选D。
小题1:这篇短文主要描述了牛仔裤的发展历史，故选C，蓝色牛仔裤的历史。