The correct answer is - Most of the imported crops in Germany had died.
In this period, Germany was in a bed economic position, and one of the factors that contributed to it was that big portion of the imported crops had died and that was also causing big problems in the food supply for the population. This triggered lots of Germans to migrate to the United States in search for better life, mainly to find work in the industrial facilities and also to have a more stable food supply. Most of the German immigrants settled in the Midwest region.