The Peace of Westphalia in 1648 constituted the starting point of the international system:  Europe adopted a specific kind of sovereignty and regular interactions among mutually-recognized sovereign states emerged. Further, these interactions developed specific patterns of relations in terms of cooperation and conflict through the normative institutionalization of mutual exchanges between states. They have evolved and developed over time as the international system geographically expanded and its numbers of political actors increased. The Peace of Westphalia incorporated the treaties of Münster and Osnabrück that officially ended the Thirty Years’ War in 1648.  Some key features of international politics have been ascribed to the content of these treaties, since they symbolized the emergence of a new international order in which sovereign states interact with each other. As can be understood from the information given the correct answer is A.

The information about the treaties which take place in the other options is as follows:

In 1555, the Peace of Augsburg was signed to reduce sectarian tensions in Europe. It sought peaceful coexistence between Roman Catholics and Protestants (at that time limited to Lutherans) and gave every prince within the Holy Roman Empire the right to choose either Lutheranism or Roman Catholicism in their own domains. However, in practice the Peace of Augsburg was not able to resolve the dispute either religiously or politically.

Between 1648 and 1789, each succession war was concluded with a peace settlement following an international diplomatic congress that included all the warring parties, The Peace of Utrecht put an end to the Spanish Succession Wars in 1713, for instance.

Imposed top-down by the victorious powers, the restoration of Europe came under threat from modern ideas introduced by the French Revolution, including liberalism and nationalism. For this reason, it was considered essential to set up a structure that would guarantee the maintenance of the Vienna settlement. To do so, the Congress of Vienna made significant arrangements for the restructuring of the international system. The major powers sought to recreate a new European political landscape that would parallel the former system and restore the balance of power.