Correct answer choice is :
B) Railroads brought crops and food to cities in the East, and settlers to farms in the Great Plains.
Step-by-step explanation:
The post–Civil War period saw the first addition of regular check routes across the American Great Plains with the development of the Union Pacific Railroad, an essential part of the first cross-country line, developed in May 1869. Railroads converted the Great Plains into an interracial part of both the United States and Canada by taking travelers, including inbound foreigners, and by bringing agricultural goods out and constructing stuff in.