What was the role of railroads in resources available

Railroads helped in making new cities grow into manufacturing centers that refined natural resources is the true statement.

Explanation:

After the railroads were constructed, many people started to settle along the railroads which resulted in growth of huge cities. America, which was an agrarian society, developed to be a manufacturing hub because of the industries that were established along the railroads.

Railroads were very helpful to carry on freight and also people. Trails of railroads enabled people  to settle and many industries were set up which made America a manufacturing Giant.  Wherever the railroads went, people started to follow and inhabited the sparsely populated

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