Question

Which of the following groups was most immediately affected by the Gadsden Purchase?
US citizens
Mexican citizens
abolitionists
slaveholders

Answer 1

i would say Mexican citizens 

Answer 2

The correct answer is:

Mexican citizens.

The Gadsden Purchase is a region the United States purchased from Mexico by the Treaty of Mesilla (1854). The acquisition incorporated lands that the U.S. wanted to develop a transcontinental railroad along a southern route.

The Gadsden Purchase was the least important territorial acquisition in the United States and settled the Mexico–United States border.

Santa Anna´s government was under financial distress and may have decide to cede territory by treaty and obtain payment instead of having the territory just seized by the U.S.