Answer:
d. steamboats, canals, railroads
Explanation:
People migrating to the West helped fuel the economic conditions. People started trading at different regions of the world. People kept of travelling and trading at different parts of the world, selling their products at different regions and buying the products of their region and again selling it in different region of the world. They do this by carrying the items and products by through different modes such as railroads, steam boats, canals, turnpikes, etc.
Most of the cotton produce ii the United States are carried over to England and sold there. The spices produced in India are traded to different parts of he world and also to England.
The western and the southern rivers in the United States are mostly used by steamboats for transporting freight and traders.
Thus, the canals and steamboats are used to connect the East to the West, whereas the West and South were binded by the railroads.
