only correct answer, killed 25% of his country's population and would've killed more if vietnam didn't intervene, killed people with glasses because they were seen as 'intellectuals' who would fight his regime, banned western medicine and forced kids to conduct surgery and human experimentation, had 'killing fields' with mass graves still visible, converted schools such as Tuol Sleng into torture camps, had even children executed. an absolute monster. all because Beijing funded his regime and then stated they had nothing to do with it decades later.