How did railroad building lead to increased division between the north and south?
a) the south had no interest in building railroads and saw the north as destroying the landscape by initiating them.
b) the south needed railroads to expand markets for their crops, but northern businessmen refused to invest there.
c) the north was increasingly a manufacturing economy and tied with the west, while the south remained agrarian.
d) the north built railroads to the west to encourage settlement there by those who were against expanding slavery.

The north had the money, the people, the resources, and the industrial power to diversify the railroad networks. So following markets and money, the north built networks to the west to expand. Also, railroads were prevailing making a rise in real estate values, increasing regional concentrations of industry, the size of business units and growth in investment banking and agriculture. Wheat production was also moving westward with the rail lines.

The south in the other hand do not have the capability to construct as much railroads as the north did so therefore there was less western expansion. As well the south had more concerns in building canals and shipping products of the states to England.

Therefore the correct answer is letter c.