In the beginning of the twentieth century, the united states had become

A) politically unstable: No, it was very stable.
B) accustomed to military involvement overseas: This phase began almost three decades later.
C) unwilling to resolve issues through diplomacy: This is likely; when the whole of Europe revelled in it. D) less interested in Latin American affairs: This is not relevant to the times then.
Hence "C)".
{one factor that needs to be kept in consideration when dealing with American involvement overseas is - being far away form all such theaters of war, ensconced safely between the two of three Oceans is the real American strength. Any weapons developed under these constraints by Americans wouldn't work in far off places demanding a different set of constrai

The answer is a. mantle