Final answer:
Radical Republicans in 1865 stood apart due to their demand for immediate equality and civil rights for formerly enslaved people. They wanted to profoundly change Southern society and ensure full rights for freed people, which was more extreme than the positions of moderates and other Americans at the time. The correct option is A.
Step-by-step explanation:
The specific position that separated Radical Republicans from both moderates and most other Americans in 1865 was that they advocated for immediate equality and civil rights for formerly enslaved people.
In contrast to moderate Republicans or conservative Unionists who may have supported gradual emancipation or other limited measures, Radical Republicans pushed for a swift and comprehensive transformation of Southern society following the Civil War.
The Radical Republicans' stance extended beyond Abraham Lincoln's more conciliatory and moderate approach to Reconstruction, calling for harsher treatment of the defeated Confederate states and punitive measures towards ex-Confederates.
During the presidential campaign of 1865, the Republican Party clearly opposed the further spread of slavery as part of their platform. This opposition to slavery expansion into new territories resonated with the broader Republican views on free labor and free soil.
The Radical Republicans were distinct in their commitment to fundamental changes in Southern society and politics. They envisioned a Reconstruction that would revolutionize the South, enforce penalties on former Confederates, and guarantee the rights of African Americans as equal citizens, including the right to vote, hold office, and enjoy legal equality. The correct option is A.