Which of the following is an external factor leading to immigration to the U. S.?

During the nineteenth century and the first quarter of the twentieth century around thirty million people emigrated from Europe to the United States. Causes of these vast movements of people are explained in this paper. The three main causes were a rapid increase in population, class rule and economic modernization. Personal reasons are mentioned and discrimination against religious and ethnic minority groups are touched upon. Two inventions, the steamship and the railroad are referred to insofar as they helped the emigrants and were a cause of hardship for the poor people of Europe. Although causes of emigration fall under the heading of historical facts, they are considered in this paper as causes of suffering for the destitute of Europe who made up the largest number of emigrants to the United States.

they remained in rural areas and worked at jobs such as lumbering or farming.

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explanation:

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