Answer :
Final answer:
Railroad expansion drove industrial progress in the late-nineteenth century in the US.
Explanation:
Railroad expansion was the principal agent of industrial progress in the late-nineteenth century in the United States. The development of railroads revolutionized transportation, linking port cities to the interior, facilitating the movement of goods, people, and resources.
The growth of cities, emergence of titans of industry like Andrew Carnegie and John D. Rockefeller, advancements in technology such as the telephone and electricity, and the shift from farm to manufacturing production all played significant roles in driving industrial progress during this period.
The expansion of the railroad infrastructure was vital for the US economy, enabling companies to transport workers and raw materials to factories, ultimately contributing to the country's economic growth.
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