Answer:
C. water routes.
Step-by-step explanation:
The first major cities in the United States typically developed near major water routes, as ships had already developed considerably during the Age of Exploration, and is large enough to transport people and material goods in long distances.
The second development was trails, followed by wagon trails, which was regularly used during the expansion west, and especially during the Age of the Gold Rush.
The third developed was the railroad routes, especially with the completion of the Continental Railroad. More railroad routes would soon spring up, which greatly sped up the westward expansion.
Highways typically describe the routes used by cars, which did not occur until around the World War I era.
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