Railroads connected cities and markets from coast to coast, making it easier for new immigrants to migrate between shifting employment opportunities is development most likely contributed to the conditions described by Riis.
<h3>What was the name of the
railroad that connected the US from coast to coast in 1869?</h3>
Railroad that tallies across the United States. The completion of the transcontinental railroad unifies the United States.
The presidents of the Union Pacific and Central Pacific railroads meet in Promontory, Utah, on May 10, 1869, to put a ceremonial last spike into a rail line connecting their railroads.
Thus, option C is correct.
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