The correct answer is C. The best country would win any international competition.
Step-by-step explanation:
Social Darwinism refers to a theory that emerged in the 19th century and stated the principles proposed by Darwin related to animal species can equally be applied to human societies. Because of this, Social Darwinists believed there were people, societies or nations that were stronger than others and because of this, these will prevail. Unfortunately, this theory was used linked to ideas such as racism, imperialism or eugenics to attack and exterminate those that were considered as weak. Considering this, the statement that describes what Social Darwinists believed is "the best country would win any international competition" because according to this theory there are strong and weak nations and only strong nations prevail over weak ones.