Question

Read the given source and answer the questions that follow : The Revolutionaries During the years following 1815, the fear of repression drove many liberal-nationalists underground. Secret societies sprang up in many European states to train revolutionaries and spread their ideas. To be revolutionary at this time meant a commitment to oppose monarchical forms that had been established after the Vienna Congress, and to fight for liberty and freedom. Most of these revolutionaries also saw the creation of nation-states as a necessary part of this struggle for freedom.

Arrange the following events in chronological order and choose the correct option : I. Defeat of Napoleon in the battle of Leipzig II. Beginning of struggle for Greek independence III. Formation of customs union Zollverein IV. Signing of Treaty of Vienna Options :