Answer:
the 3 one the only one that make sence
Explanation:
The Columbian Exchange had positive and negative consequences.
Some of the positive consequences were the introduction of different nutrients and food supplies into the Old World, such as corn or potatoes. This improved the diet of most Europeans, leading to a population growth in the next generations.
However, Europe benefited more than the Americas, for some of the negative consequences about the Columbian Exchange were the introduction of diseases into the continent and the slavery of African populations into the Americas.
Evangelism affects diffusion from a world-wide evangelicalism just after the Second World War.
A) higher debts for farmers
Not so much happened during the boom crop production in 1870s, but the main result of this event were the crop prices going down. The fresh food prices decreased due to the increased of food supply which eventually led the farmers to have higher debts.