Gadsden purchase is the correct answer, as secured land for a route for a western railroad.
Gadsden purchase is a region of the Arizona and New Mexico, that has been acquired by the United States through the Treaty of Mesilla.
Gadsden purchase basically provided the land that is necessary for the western railroad.
It also attempted to work outs on the conflict that was remained after the was between the Mexican-American.
Learn more about the Gadsden purchase here:-
https://brainly.com/question/1090355
#SPJ1
