Dr. B.R. Ambedkar is the correct answer. He was the chief architect of the Indian Constitution and expressed this view during the Constituent Assembly debates. His statement reflected his concern about ensuring equality in the face of deep-rooted social and economic disparities.

Option 2, Jawaharlal Nehru, although an influential leader in the Constituent Assembly, is not associated with this particular statement.

Option 3, Mahatma Gandhi, was the leader of the Indian independence movement, but he was not a member of the Constituent Assembly and so, would not have made such a statement there.

Option 4, S.P. Mukherjee was a member of the Constituent Assembly and later the Minister for Industry and Supply in Nehru`s cabinet. However, this statement was not made by him.

So, the statement about India entering a life of contradictions was declared by Dr. B.R. Ambedkar, highlighting the societal contradictions that India was to face on becoming a republic.