Final answer:
The correct answer is option a) Set up a naval base.
Step-by-step explanation:
In the early 20th century, as part of the Platt Amendment, the Cuban government was required to allow several concessions to the United States, including the right for US intervention in Cuban affairs to "preserve Cuban independence" and to maintain 'protection of life, property, and individual liberty.' Among these, Cuba had to agree to give the United States a naval base at Guantánamo Bay, which remains under U.S. control to this day.
As a result, Cuba was prohibited from signing any treaties that would jeopardize its independence or allowing any foreign military access, as well as from accruing certain levels of foreign debt. This heavily influenced Cuban independence and the US-Cuban relationship for decades to follow.
The Platt Amendment was eventually partially repealed as a part of Franklin D. Roosevelt's Good Neighbor Policy, but the lease of Guantánamo Bay remained. Throughout history, the United States has been actively involved in Cuban affairs, even to the point of supporting dictatorships that served its interests, as in the case with Fulgencio Batista, until the Cuban Revolution led by Fidel Castro changed the political landscape of both countries.