How did railroad expansion make natural resources more available in the United States?

Railroads connected resource-rich areas with cities and towns, allowing materials such as coal, timber, and iron to be shipped over long distances. This made existing natural resources more available to people and businesses. Railroads did not create more resource deposits, so the correct choice is “by making it possible for natural resources to be transported to different cities and towns.”

AI-written and checked against the verified answer.