Answer:
B: Farmers can produce more crops from the same amount of land.
Step-by-step explanation:
American farms grew larger and more productive at the same time that the global demand for their crops, and the food made from those crops, accelerated. The United States exported 6,988,000 metric tons of corn in 1960. In 2007, the United States exported almost nine times that amount: 61,913,000 metric tons of corn. Corn exports have declined since 2007 because the growth of the ethanol industry has kept more of the corn crop at home. To meet the growing global demand for corn on basically the same amount of land, American farmers improved the productivity of their crops: corn yields, as measured in tons per hectare, more than doubled from 1960 to today.
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