单项选择题

Once a young man bought a pair of trousers for himseif. The size of the new trousere was two incbes Ionger than his. So be asked his mother or either of his two sistem Io shorten (使变短) them. Tbey all smd nothing to bim because they were too busy. But none of tbem forgot the Irousers. They did it one after another as soon us they were free whhoul rolling the other. The next morning when the young tne put on the trousers. be fgund the trousers had been four incbes short.