The three main groups that had access to political power in the South during Radical Reconstruction were

This option inaccurately includes the planter class, who were traditionally opposed to Reconstruction efforts and sought to maintain their pre-war social order. Thus, they did not hold political power during this period, which was characterized by a struggle against their influence.

While formerly enslaved people did gain political power, the planter class again undermines this choice as they were generally resistant to the changes brought about by Reconstruction. Small farmers, although present, were not a dominant political group compared to the other entities mentioned.

This selection includes carpetbaggers, who were indeed part of the political scene, but the inclusion of the planter class negates its accuracy. Planters sought to retain their power and influence, often working against the interests of the groups that were actually gaining political access during Reconstruction.

The term "Yankees" typically refers to Northerners in a general sense, which lacks specificity in this context. Additionally, former Confederate officials were largely excluded from political power during Radical Reconstruction, making this option incorrect.