Detailed Solution:
The correct answer is “1, 2 and 3”.
The following methods have been used to estimate poverty in India:
1) Head Count Ratio: This method calculates the proportion of the population that is below the poverty line.
2) Calorie Intake: Poverty estimation has often been based on the minimum calorie intake needed for sustenance, linking it to a poverty line.
3) Household Consumption Expenditure: This method assesses poverty based on the consumption expenditure of households and compares it to a defined poverty line.
Per Capita Income has not been used directly as a method to estimate poverty in India.