The answer is B
Hope this helps:)
Under the Articles of Confederation, Congress lacked the authority to regulate commerce, making it unable to protect or standardize trade between foreign nations and the various states.
I think that the best answer is the geographic location: many other countries (Sweden for example) have tried being neutral at different times but did not manage to: but the fact that the US has only two boundaries, and that both other countries also have a history of fighting from independence from a European power, makes it possible that unless US decideds to get involved in international politics, it can be "left alone".
