During the Gilded Age, railroad expansion significantly affected the prices of goods primarily because shipping products by railroad was much cheaper, which led to a decrease in the cost of goods. The expanded rail network made it possible to transport goods over long distances quickly and efficiently, reducing shipping costs and ultimately leading to lower prices for consumers. This accessibility and affordability contributed to widespread economic growth during that period. Therefore, the correct statement is:
Shipping products by railroad was much cheaper, and the cost of goods decreased.