Which development had the greatest impact of territorial growth , economic growth,, industrial growth during the years after the Civil War?(SSUSH12a) Canals Railroads Telephones Airplanes

## Step 1<br />The question is asking us to identify which development had the greatest impact on territorial growth, economic growth, and industrial growth during the years after the Civil War. The options provided are canals, railroads, telephones, and airplanes.<br /><br />## Step 2<br />We need to consider the historical context of the period after the Civil War. During this time, the United States was undergoing significant changes and expansion. The development of infrastructure was crucial to support this growth.<br /><br />## Step 3<br />Among the options provided, railroads had the most significant impact. Railroads allowed for faster and more efficient transportation of goods and people, which facilitated territorial growth by enabling the expansion of settlements and the establishment of new towns and cities.<br /><br />## Step 4<br />Railroads also had a profound impact on economic growth. They allowed for the rapid movement of raw materials to factories and finished goods to markets, which increased productivity and profitability.<br /><br />## Step 5<br />Lastly, railroads played a crucial role in industrial growth. They provided a means for industries to transport their products to markets, which increased production and profitability.