PRUSSIAN KING
The answer is: c. Prussian king
Germany was finally united under the control of a Prussian king, specifically King Wilhelm I of Prussia, who was crowned as the first German Emperor (Kaiser) in the Hall of Mirrors at the Palace of Versailles in 1871. This event marked the end of the German Confederation, a loose alliance of German states that had existed since the Napoleonic Wars, and the beginning of the German Empire, a unified nation-state under the rule of the Prussian monarchy.
Germany was not a democracy at this time, and the Prussian king was not elected by the people. Rather, he inherited the throne by virtue of his birth into the royal family. It was not until after World War II, in the post-war period, that Germany became a democratic federal parliamentary republic with a president as its head of state.
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