Final answer:
The period in which former slaves were shown casting a vote was the Reconstruction Era, which saw increased democratic participation for African Americans before the setback of the Jim Crow Laws. The correct answer is a) Reconstruction Era.
Step-by-step explanation:
The correct answer to the question of former slaves shown casting a vote during which historical era is a) Reconstruction Era. This period was marked by significant changes in voting rights and governance, especially for African Americans. After the Civil War, during Reconstruction, African Americans began to win elections and hold positions of power in the South for the first time.
The Voting Rights Act and additional legislation aimed to eliminate racial discrimination in voting, marking a transformation from an all-white, pro-slavery, Democratic stronghold to a more inclusive Republican-led political landscape.
However, this progress in democratic participation for African Americans was eventually undermined by the establishment of the Jim Crow Laws towards the end of the Reconstruction period and the resurgence of white supremacy.