The correct answer is option 4. Explanation & Key Takeaways: • The National Sample Survey Organization (NSSO), since its inception in 1950, does the measurement of employment/unemployment in India. • The National Sample Survey Organization (NSSO) provides three different estimates of employment and unemployment based on different approaches/reference periods used to classify an individual’s activity status. These are the- • Usual status approach with a reference period of 365 days preceding the date of the survey. • Current weekly status approach with a reference period of seven days preceding the date of the survey. • Current daily status approach with each day of the seven days preceding the date of the survey as the reference period. • In order to find out whether an individual is employed or unemployed, it needs to be first determined whether h/she belongs to the ‘Labour Force’ or not, which in turn depends on the Activity Status of the individual during the chosen reference period. • Activity Status refers to the activity situation in which the individual is found during the reference period with respect to his participation in economic or non-economic activities. • The labour force (also called workforce) is the total number of people employed or seeking employment in a country or region. One is classified as ‘not in the labour force if he or she was engaged in a relatively long period in any one of the non-gainful activities. Hence option 4 is correct. • Unemployment rate is the percentage of the labor force that is without work.