The correct answer is option 2, Adolf Hitler. Adolf Hitler was a German politician who rose to power in the 1930s and became the leader of the Nazi Party. He is the main advocate and leader of Nazism in Germany. Nazism is a far-right ideology that was characterized by authoritarian and totalitarian rule, anti-Semitism, and the belief in German racial superiority. Hitler and the Nazi Party implemented policies that led to the persecution and extermination of millions of people, particularly Jews, during the Holocaust. It is important to note that while other political figures such as Fedrick William IV, Bismark, and William III played significant roles in German history, they were not the main advocates of Nazism like Adolf Hitler.