The Congress of Vienna was convened with the purpose of reshaping the map of Europe. The participating nations wanted to reorganize Europe in order to bring back the balance of power that had existed between the nations a century earlier so as to avoid any large scale wars like the ones they had just seen during the Napoleonic Wars.

The Congress of Vienna was meant to undo the effects of the French Revolution on Europe and put royal families back in control of the nations of Europe. It also sought to give large territorial gains to the victorious powers of Continental Europe, mainly Austria, Prussia, and Russia. The idea was that if these nations were powerful enough they could keep any future threat from France in check. They also wanted to replace the Holy Roman Empire with a newer German Confederation since the Holy Roman Empire was dissolving.

While all of these men were present at the negotiations in Vienna, the chairman would be the leader of the Austrian Delegation. As Vienna was the capital of Austria, it was only logical to have Klemens Wenzel von Metternich, the Austrian Foreign Minister chair the negotiations and serve as intermediary between different delegations.

Spain was not considered one of the Great Powers. While they were signatories of the Congress of Vienna, they were not invited to take part in large parts of the negotiations. Spain's power had waned and Spain was not considered a militarily powerful nation, as it had been two centuries earlier.

Essentially every nation and princely house had a representative in Vienna for the Congress. While the bulk of the agreements excluded those who were not part of the Great Powers these nations still wanted to get the most out of the final agreements. The concentration of nations brought out people from other factions such as religious organizations, corporations, advocacy groups and many others.

The Treaty of Augsburg did not create a peace between Austrians and Germans that would last until the 18th Century. Austria would be consistently involved in the 30 Years War, which broke out in 1618. All other option are factual stipulations and effects of the Peace of Augsburg which would remain effective until 1618 and the 30 Years War. 

Although the Secret Protocol was to be a secret, it was agreed that only Nazi Germany and the USSR (the signatories) would be privy to it. The other members of the Axis (Italy and Japan) were not told. All other answers were actual parts of the treaty. 

Of all the choices only the EDC was never ratified, although a provisional treaty was signed between several West European states. It failed to be ratified by the French government in 1954 and thus never went into effect. NATO largely filled the role that the EDC was meant to, and thus contributed to European Integration by connecting most of Western Europe through a collective defense organization. The ECSC, EEC, and EU were all ratified and went into effect in 1952, 1957, and 1993 respectively.