What is the primary purpose of the Book of Ruth within the broader narrative of the Old Testament, beyond being a love story?

A To provide a detailed historical account of agricultural practices in ancient Israel. B To demonstrate the importance of strict adherence to Jewish dietary laws and rituals. C To illustrate God's providential care and inclusion of Gentiles (non-Israelites) into the lineage of King David and ultimately Jesus Christ, highlighting themes of loyalty and redemption. D To serve as a cautionary tale against intermarriage with foreign women, emphasizing the dangers of cultural assimilation.