TOEFL Reading: ETS-TOEFL阅读机经 - 3EU6267163DD3U31L$

According to paragraph 2, which of the following caused the food supply to increase in most of Western Europe during the nineteenth century? A. Replacement of seventeenth-century farming techniques with more modern ones B. Improved grain harvests in most European countries C. Reduced demand for food as a result of a decreased population D. Use of new land to grow crops