V M Dandekar and Neel Kanth Rath were well-known for their study on poverty in India. The researchers conducted an influential study that shed light on the extent and causes of poverty in the country. Their research provided valuable insights into the demographic and economic factors that contributed to poverty in different regions of India.

Option 1, study on the spread of the Green Revolution, is incorrect. While the Green Revolution was an important agricultural development in India, it is not directly associated with the work of Dandekar and Rath.

Option 2, advocacy of nuclear power, is incorrect. Dandekar and Rath`s research was focused on poverty, not on nuclear power or any other energy source.

Option 3, advocacy of liberalization, is incorrect. The researchers did not advocate for any specific economic policy such as liberalization. Their work was primarily aimed at understanding and addressing poverty in India.

It is important to note that while the correct answer is provided, there is not much explanation provided in the question to fully understand the context and significance of Dandekar and Rath`s study on poverty in India.