Final answer:
The military intervention in Cuba during the Spanish-American War made it possible for American businesses to invest in Cuba.
Step-by-step explanation:
American businesses were able to invest in Cuba due to the military intervention in Cuba during the Spanish-American War. The United States became involved in Cuban affairs after the USS Maine exploded in Havana harbor, officially entering the war. This action got the attention of American businesses who saw the opportunity to invest in Cuban agriculture and benefit from the country's economic reforms.