In the book of Ruth, beyond the lineage of David, what deeper theological theme is emphasized through the character of Boaz and his actions toward Ruth?

A The extension of kindness, redemption, and inclusion to those considered outsiders, reflecting God's grace. B The importance of maintaining strict social boundaries to preserve cultural purity. C The fulfillment of specific legal obligations without regard for personal relationships. D The superiority of Israelite customs over foreign traditions in matters of marriage and inheritance.