Sir BN Rao was the Constitutional Advisory to the Constituent Assembly of India.

Background:
After India gained independence, the Constituent Assembly was formed to draft the Constitution of India. It consisted of representatives from various political parties, communities, and regions.

Constitutional Advisory:
The Constituent Assembly appointed a Constitutional Advisory Committee to provide guidance and assistance in drafting the Constitution. Sir BN Rao, a renowned jurist and civil servant, was appointed as the chairman of the committee.

Role:
The role of the Constitutional Advisory Committee was to study the constitutions of other countries and provide suggestions on the structure and content of the Indian Constitution. Sir BN Rao was instrumental in providing valuable inputs on various aspects of the Constitution, including fundamental rights, directive principles, and the powers of the President and Prime Minister.

Significance:
The contribution of the Constitutional Advisory Committee, and Sir BN Rao in particular, was crucial in the drafting of the Indian Constitution. The Constitution of India is considered one of the most comprehensive and inclusive constitutions in the world, and the role of the Constitutional Advisory Committee in its formulation cannot be overstated.

Conclusion:
Thus, Sir BN Rao played a significant role as the Constitutional Advisory to the Constituent Assembly of India and his contribution to the Indian Constitution will always be remembered.