The correct answer is: "Due to the Nuremberg Laws"
During WWII, the German Nazy party headed by Hitler conducted the Holocaust against the Jewish, through which they aimed to exterminate them all. Crimes related to the Holocaust, which were considered crimes against humanity, were mostly imputed to those major war criminals.
Explicit legal discriminations against the Jewish population started in 1935 with the enactment of the Nuremberg Laws that considered them second-class citizens and that aimed to protect the purity of the German Blood, for example, by prohibiting marriages between Jewish and German people. From that moment on, discriminative regulations, progroms, establishment of ghettos and finally, mass-murders and extermination, were performed by the Nazis against the Jews.