D. established that genocide was an international crime.
Nuremberg trials were held between 1945 and 1949, with the aim of prosecuting German military leaders, political officials and financiers for the crimes they committed during the Second World War. The judges from the Allied Powers were the United Kingdom, France, the Soviet Union and the United States. Although some of the procedural innovations were controversial, the Nuremberg trials are considered a milestone for the establishment of a permanent international tribunal, in order to prevent subsequent, any possible genocides and other war crimes.
The answer is: D.
