During his formative years, who served as the guardian and mentor of Chhatrapati Shivaji Maharaj?

The correct option is Dadoji Konddeo.

Explanation:
During the formative years of Chhatrapati Shivaji Maharaj, Dadoji Konddeo served as his guardian, administrator, and mentor. He was entrusted by Shahaji Raje (Shivaji's father) with the management of the Pune estate and the upbringing of young Shivaji alongside his mother, Maharani Jijabai.

Key points regarding Dadoji Konddeo's mentorship:
1. Administration & Governance: He trained Shivaji Maharaj in practical administration, land management, law, and justice.
2. Military Training: He supervised Shivaji's initial training in weaponry, military tactics, and horsemanship.
3. Guidance: Under his guidance, Shivaji Maharaj gained hands-on experience in managing local affairs, which laid the foundation for establishing Hindavi Swarajya.