They spread industrial technologies and products across wide areas, is the right answer.
Explanation:
The Industrial Revolution initially began in Europe and then spread to other parts of the world such as the United States, Japan etc. The following are the roles played by the railroads during the Industrial Revolution:
Opened new ways for the settlement of the West.
The development of railroads spread new technologies and products throughout wide areas.
The railroad provided new job opportunities and tied together various towns.
