The growth of national railroads in the late 1800's had what major effect on the united states?
a.) it increased the number of immigrants who relocated to the east coast of the united states.
b.) it decreased the accessibility of people in the western united states to goods made in europe and shipped to port cities such as new york.
c.) it shifted the economic system of the united states from locally-based to nationally-based.
d.) it inhibited the growth of the western cities such as denver and dallas.