Which of the given statements about 'The Treaty of Vienna' of 1815 is/are correct?

(I) In 1815, representatives of the European powers – Britain, Russia, Prussia, and Austria – who had collectively defeated Napoleon, met at Vienna.

(II) The Vienna Congress was hosted by the Austrian Chancellor Duke Metternich.

(III) The objective of the Treaty of Vienna was to restore the balance of power in Europe and prevent the imperial ambitions of European empires similar to Napoleonic France.