Q. Which was the first Backward Classes Commission that helped define Scheduled Tribes?
Answer: Kalelkar Commission
Notes: The Kalelkar Commission (1953) was India's first Backward Classes Commission, examining social and educational backwardness and contributing to the definition of Scheduled Tribes. Later commissions like Mandal focused on Other Backward Classes. Sarkaria dealt with Centre-State relations. Thus, Kalelkar holds primacy in backward class classification related to Scheduled Tribes.