Final answer:
The obstacle faced by the Union Pacific Railroad workers was that they needed to ship large quantities of essential raw materials such as D. iron and wood to the construction sites for building the railroad tracks.
Step-by-step explanation:
The obstacles faced by the Union Pacific Railroad workers was the necessity of having to ship large quantities of essential raw materials to the construction sites for building the railroad tracks.
The main raw materials were not silver and wood (Option B), nor was it coal and oil (Option A), and not oil and iron (Option C). The correct answer is iron and wood (Option D). These two materials were crucial in the construction of the railroad.
For instance, in the mid-19th century, railroad construction triggered an increase in demand for coal, iron, and steel. Iron was used in manufacturing the railroad tracks, while wood was needed for the railroad ties and infrastructure .
The United States developed an extensive railroad infrastructure that stimulated growth in the coal, iron, wood, and steel industries.Moreover, the Union Pacific Railroad, commissioned as a result of the Pacific Railway Act,
Had to bring in large quantities of iron and wood for the construction of railroad tracks. Consequently, these raw materials had to be shipped in large amounts to meet the massive demand required for the completion of the ambitious project.
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