Final answer:
The sinking of the USS Maine had the greatest effect in contributing to the Spanish-American War.
Step-by-step explanation:
The sinking of the USS Maine had the greatest effect in contributing to the Spanish-American War. The USS Maine, an American battleship, exploded in Havana Harbor in 1898. While the cause of the explosion was never definitively determined, it was widely blamed on Spain, leading to public outrage in the United States and ultimately the declaration of war against Spain.
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