B. Opening up the eastern front
The growth of railroads impacted American society after the Civil War in this way: C
. The oil and steel industries gained considerable political and economic power.
The advent of the railroad system after the Civil War led to an increase in migration across the counties in the country.
Also, there was a major shift in the migration from the rural to the urban areas. Most people who migrated were in search of jobs.
Thus, there was an increase in the manufacturing industries and so, the oil and steel industries gained more political and economic power.
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Democratic Party supports the west
In 1890, Mary E. Lease led the Farmers' Alliances to D. revolt against high mortgage rates.