Final answer:
Business interests and the use of Cuban harbors were important factors leading to US involvement in the Spanish American War.
Step-by-step explanation:
The ONE statement that best describes the causes of the Spanish American War is: Business interests and the use of Cuban harbors was important to US trade and military might. The United States had economic interests in Cuba and wanted to protect its trade and military access to the island. The US government viewed the situation in Cuba as a threat to its economic and strategic interests, leading to their involvement in the war.
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