The four correct statements that describe causes of the Spanish-American War are:
- The US blamed Spain for the USS Maine explosion.
- US newspapers exaggerated stories so citizens would support the war.
- The Monroe Doctrine did not allow European interference in the Americas.
- US businesspeople had invested in Cuba, particularly in sugar.
(Note: The statement about US businesspeople relying on Cuba for oil is not entirely accurate, as their investments were primarily in sugar and tobacco. The statement about Spain being closely allied with Mexico during the revolution does not accurately represent the context of the war.)