To combat reconstruction reforms, some southerners organized
a. white supremacy groups.
b. the freedmen’s bureau.
c. a new republican party.
d. the civil rights movement.

Option A, White Supremacy Groups, is the right answer.

Explanation:

During the Reconstruction Era, the White Supremacy groups were formed to spread terror among the members of racial minorities, who lived in the Southern states. One Such group was the Ku Klux Klan, who was known for the kidnapping of the Black citizens to either kill or torture them. Such White Supremacy groups did not want the blacks to be provided with the right to vote and share the rights and privileges of American Citizens. In short, they believed that all the powers should be held by the Whites.

d.)   when the us left nato after the end of the cold war and they had to evolve to focus on more humanitarian measures with the smaller budget