At the time of Second Industrial Revolution, railroad expansion modified settlement in the West.
Second Industrial Revolution is the time period when the steel production, electricity and petroleum are in the advancement stage and the innovation change the society. Railroad are expanded with the cost efficient methods, which gives more chance to people to travel from rails.
Thus, option D is correct.
For more information about Second Industrial Revolution, click here:
https://brainly.com/question/7154211
#SPJ2
