Final answer:
The national telegraph system was the most important advance in communications in America prior to the Civil War.
Step-by-step explanation:
True
The national telegraph system was indeed the most important advance in communications in America before the Civil War. It revolutionized long-distance communication by enabling messages to be sent quickly across vast distances.
An example of its importance is the impact it had on news dissemination during the Civil War. News from the battlefield could be transmitted rapidly to the rest of the country, shaping public opinion and influencing decision-making.
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