单选题 ______ that they may eventually reduce the amount of labor needed on construction sites by 90 percent.
【正确答案】 A
【答案解析】[解析] so/such...that...表示“如此……以至于……”，区别在于so修饰形容词或副词，而such修饰名词。另外，so位于句首时，后面的句子要用倒装结构。故选项A为正确答案。