The correct answer is Dadabhai Naoroji. Dadabhai Naoroji in his book, "Poverty and unBritish Rule in India" made the earliest estimation of the poverty line. He estimated Rs, 16 to 35 per capita per year. The poverty line proposed by him was based on the cost of a subsistence or minimum basic diet (rice or flour, dal, mutton, vegetables, ghee, vegetable oil, and salt). Important Points Dadabhai NaorojiHe is also known as the Grand Old Man of India. He was the 2nd and 9th President of the Indian National Congress. He put forward the 'drain of wealth' theory in which he stated that Britain was completely draining India. Additional Information Mahatma GandhiHe is known as the 'father of Nation'. He was the primary leader of India's independence movement and also the architect of a form of non-violent civil disobedience that would influence the world. Rajendra PrasadHe was the first president of India. He was one of the first to receive the Bharat Ratna in 1962. Raja Ram Mohan RoyHe is considered the 'father of the Indian Renaissance. He is renowned for his pioneering role in opposing practices like Sati, child marriage, and social divisions.