The dramatic growth of american cities between 1800 and 1860 a. resulted in unsanitary conditions in many communities. b. created sharp political conflict between farmers and urbanites. c. contributed to a decline in the birthrate. d. forced the federal government to slow immigration. e. put an end to the frontier era.

The correct answer is the option A

Explanation:

The Industrial expansion and population growth radically changed the face of the nation's cities. Noise, traffic jams, slums, air pollution, and sanitation and health problems became commonplace.The wealthy lived in urban mansions while the poor crowded into tenement houses, apartment buildings with tiny rooms, no ventilation, and poor sanitation.

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