Answer:
A. It brought about the decline of the Federalist Party.
Explanation:
The effect of the Hartford Convention is which was held between December 1814 to January 1815 was widely known to be based on President James Madison’s mercantile policies and the progress of the War of 1812, including the unacceptable position of the political situation of the country more specifically national government power shifting to South.
However, following the unexpected victory in the Battle of New Orleans, and the secret nature of the Hartford convention, brought about the decline of the Federalist Party.
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