Answer:
Right choice is:
It warned European nations to stay away from Western nations.
Step-by-step explanation:
The Monroe Doctrine is a concept that sees any intervention of extrarregional powers (mainly of Europe in 1823) in the affairs of the nations of the Western Hemisphere as a threat to the United StatesĀ“ security. It also states that the US would not intervene in the conflicts or issues of the European powers.