问题
单项选择题
What was one result of the increased use of machinery on farms of the United States
A．Prices for farm produce rose.
B．Farmers became more dependent on loans from banks.
C．Jefferson established government programs to assist farmers.
D．Farmers relied less on foreign markets.
答案
参考答案：B
解析：因果关系的判断。根据文章第七句“…revolutionary advances in farm machinery have vastly increased production of specialized crops…”及第八句“By raising and selling specialized crops…achieve a much higher standard of living but at a price．”可知，其逻辑关系是农业机械化的进步使专门作物的产量提高，而种植和销售该作物又可提高农民的生活水平，但这种变化也使农民付出了代价。后面具体列举了各项事实，实际上就是前面变化产生的结果，其中包括选项b的内容，因此该项是正确答案。 注意：根据暗示因果关系的单词或短语做出正确的因果判断。如本文中上下句间at a price(付出代价)的使用，暗示了前后句问存在因果关系。