题目

For over one hundred and fifty years, Americans of all social classes have worn blue jeans. __1__Whether they are worn for work or for fashion today. Strauss' invention continues to be popular not only among Americans but also among people around the world. Levi Strauss was born in Germany in 1829. __2__ He grew up in Kentucky before moving to New York in 1847. Before becoming an American citizen and moving to the West in 1853, Strauss worked in his brother's dry goods business. This gave him a chance to produce his famous invention. After the gold rush of 1849, Strauss decided to move Such things ________ allowed to happen again.A.ought not to beB.not ought to beC.ought to not beD.ought to be not