How does the story of Rizpah, who guarded the bodies of her sons after they were executed, primarily function within the broader narrative of 2 Samuel 21?

A It primarily highlights David's cruelty and disregard for justice. B It mainly serves to emphasize the power and authority of King Saul's lineage. C It illustrates the severity of God's judgment on Israel for Saul's broken oath and David's eventual act of atonement. D It primarily showcases Rizpah's personal grief and mourning without broader implications.