I believe it is B. The purpose establishment of the League of Nations was to resolve international conflicts without war.
Choice A doesn't really make sense because neutral nations don't join war alliances; they remain neutral. Choice C and D actually would lead to more wars because Germany was bitter about being forced to accept the defeat. They further had to pay for the reparations, which wouldn't make anyone happy.
<span>The 1920s were an age of dramatic social and political change. For the first time, more Americans lived in cities than on farms. The nation's total wealth more than doubled between 1920 and 1929, and this economic growth swept many Americansinto an affluent but unfamiliar “consumer society.”</span>
