America’s were looking to improve their transportation systems in the early 1800s primarily so that they could:

a. reduce the amount of traffic on over-crowded highways.
b. support growing immigration to the united states.
c. take advantage of a national market economy by getting their goods to market more easily.
d. defend the country from a potential attack by mexico.

The correct answer is C, Take advantage of a national market economy by getting their goods to market more easily.

Explanation:

There were many reasons to improve the transportation system at the beginning of the 1800s. One of them was to improve the American trading system.

As the expansion towards the West increased and more goods were produced in that area, there was a growing need for better transportation of the production. That's why there was a great number of constructions of roads, canals, and later railroads, that transported goods to the East Coast commerce.