Final answer:
One main reason that led to the French Revolution of 1789 was the financial strain caused by King Louis XVI's assistance to the U.S. in its War for Independence.
Step-by-step explanation:
A main reason that led to the French Revolution of 1789 was King Louis XVI's struggle to cover the expenses of helping the U.S. in its War for Independence. France's involvement in the American Revolution created a significant financial burden on the monarchy, leading to economic hardships for the French people. The situation was exacerbated by a regressive tax system and widespread inequality, which fueled social unrest and revolutionary sentiments.
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