Final answer:
The major consequence of the conflict during Reconstruction was that President Johnson was impeached by the House due to his violation of the Tenure of Office Act.
Step-by-step explanation:
A major consequence of the conflict between President Andrew Johnson and the Radical Republicans during Reconstruction was (a) President Johnson was impeached by the House of Representatives. This conflict reached a peak when Johnson attempted to remove Secretary of War Edwin Stanton, violating the Tenure of Office Act, leading the House to impeach him in 1868. Although Johnson was impeached, he was not convicted and therefore remained in office.