The correct answer is - d. khmer rouge.
The movement that called itself as Khmer Rouge under the guidance of the communist leader Pol Pot was responsible for the death of an estimated 1.7 million people in the Southeast Asian country of Cambodia. Using few different techniques they managed to commit a genocide of the Vietnamese population in Cambodia, but also they killed lots of Cambodians as well that were not on the same opinion as them. Pol Pot and the Khmer Rouge are recognised as one of the most evil leaders and organizations in the human history because of their brutality.
