Answer:
D, C, and A.
Explanation:
During the late 1800s new ways of American farming improved thanks to the development in farm technology and machinery. The railroad system made possible the transportation and commercialization of goods from the country to the cities. There was a replacement of the horse power, which was used to plough the land by the steam tractor, in which it allowed farmers to introduce a great variety of crops and wheats.
I think it's the revolutionary war.
True is your answer have a nice day!!
