Answer:
it opened up the west to the rest of America
Explanation:
According to Dr. K the trains played an important role in developing the economy of the West by opening the West up to commercial activities in large quantities across the whole of America and also neighboring countries.
The trains ensured that the movement of goods and services in and out of the west was efficient and reliable and this played a huge role in the economic boost experienced in the West during this Era. it also encouraged the settlement and the arrival of migrants in the west as well.
