Final answer:
One of the greatest problems that John Adams and the Federalists faced in the election of 1800 was the increased public debt brought on by war preparations.
Step-by-step explanation:
John Adams and the Federalists faced several problems in the election of 1800. One of the greatest problems was B. Increased public debt brought on by war preparations. Adams had been involved in war preparations, which led to a significant increase in public debt. This was a major concern for the Federalists and contributed to their challenges in the election.
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