单项选择题The biggest city in the U. S. is ______.
单项选择题Tile finest example of Hawthorne's symbolism is the recreation of Puritan Boston in______.
单项选择题The decrease in world food prices was a result of ______.
单项选择题The main reason for the rise in food prices is that ______.
单项选择题What did the future look like for Britain's food production at the time this article was written