It could be argued that Congressional Reconstruction was more about political power than racial equality. Even though Congressional Reconstruction is going to help African-Americans gain new freedoms in American society, it is ultimately based on the Northern Republicans desire for political power. Many members of the Republican Party, known as Radical Republicans, wanted to punish the South for their role in starting the Civil War. In this case, the Radical Republicans wanted to ensure that after this war, the individuals who lead the secession movement in the Southern states would not gain power. This is why many Republicans refused to include newly elected Southerners in Congressional affairs during the Reconstruction period.
D. Europeans determines that African slaves actually produced
The answer is D! Richard Nixon resigned in shame :)