Which schedule of the Indian Constitution allows different tribes complete autonomy of preserving their policies and customary laws?

Sixth Schedule

The correct answer is option (3) - Sixth Schedule

The federal system adopted by India is a flexible arrangement. While most of the states have equal powers, there are special provisions for some states like J&K and the states in the North-East. The Sixth Schedule of the Constitution allows different tribes complete autonomy of preserving their practices and customary laws.