The correct answer is - B-Ireland.
During this period the United States saw a mass migration towards them from Ireland. This was mainly due to the potato famine. The potato famine caused a big percentage of the Irish population to die, and most of the population to be on the verge of existence because of lack of food. This resulted in mass migration out of the country in search for better life and of course for a place where there always be a food on the table.
