In the Gospel of Luke, what is the primary theological significance of Jesus' parable of the Prodigal Son (Luke 15:11-32)?

A To demonstrate the importance of financial responsibility and managing inheritances wisely. B To illustrate the dangers of worldly temptations and the need for constant vigilance against sin. C To reveal God's boundless mercy, forgiveness, and unconditional love for repentant sinners, regardless of their past actions. D To highlight the social hierarchy and the expected roles of sons within a patriarchal society.