Explain the meaning of this cartoon for a reader in 1867.

AIt demonstrated that Andrew Johnson was an ineffective leader because of his interest in books.
BIt illustrated that Andrew Johnson's vetoes of legislation he labeled unconstitutional were overridden by Congress.
CIt illustrated the need to reform the U.S. Constitution because it was too complex for Reconstruction.
DIt validated the U.S. Constitution as a powerful document that was capable of removing political leaders.