How should the rebellious Southern states be reintegrated, both politically and economically, into the union?

The correct answer to this open question is the following.

Although there are no options attached, we can say the following.

The rebellious Southern states would be reintegrated, both politically and economically, into the union in the following way.

After the end of the American Civil War, in 1893, Lincoln created the "10 percent plan," which represented the beginning of the reunification process. It required that 10 percent of the southerners that voted in the election of 1890 to take an oath of allegiance to the Union. If that happened, then the southern states could create their own state constitutions. US President Abraham Lincoln also ordered Reconstruction for the Southern States and gave these former Confederated states leeway to do Reconstruction at their own pace.

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