How did the Peace of Westphalia contribute to the rise of nation-states?

Which action best represents the policy of appeasement followed by britain and france prior to the start of world war ii? (a)allowing hitler to annex the sudetenland as part of the munich agreement (b)signing the nazi-soviet pact binding hitler and stalin to peaceful relations (c)sending troops to fight with the liberals during the spanish civil war (d)forbidding the sale of arms to any nation at war