The failure was the result of maintaining martial law in the South greatly weakened the U.S.military. hence option A is correct.
Restoration of the Union, reform of southern society, and adoption of progressive laws promoting the rights of emancipated slaves were the three main goals of reconstruction.
The agency was unable to implement all of its plans due to a lack of finance, Reconstruction politics, and race relations, and it was unable to provide actual racial equality or long-term protection for blacks.
Thus, option A is correct.
Learn more about the Reconstruction process:
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