The statement that best explains why the Hutu-led government in Rwanda tried to kill the Tutsi population during their civil war is: "The Tutsi-led rebel group was trying to overthrow the government."
This reflects the context of the Rwandan civil war, where the Hutu-led government viewed the Tutsi population and the rebel forces as a threat to their power and control, leading to the genocide against Tutsi civilians. The other statements do not accurately capture the root motivations behind the genocide.