Respuesta :

It would be the "Monroe Doctrine" that  stated among other things that Europeans should not interfere with American nations, since this was an assertion of US dominance in the region. 

The correct answer is:

The Monroe Doctrine.

The Monroe Doctrine was a United States policy that opposed European colonialism in the Americas. It declared that farther attempts by European countries to take control of an independent state in North or South America would be seen as hostile.

At the same time, the U.S. would acknowledge and not interpose with existing European colonies neither interfere in the internal affairs of European countries.