The statement that describes how the transcontinental railroad affected the United States during the late 1800 is:
The transcontinental railroads were a important invention in the 1800s in America as it helped connect the people who were traveling to and from the American coasts.
This brought about a lot of new settlers in the West which brought about the rapid settlement and growth of the towns in the West and it also helped commerce to boom.
This was because food was moved from the East Coast to the West which boosted both local and international trade and let the people travel through a route that was not available before.
Therefore, the correct answer is option A
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