The correct option is Arunachal Pradesh.
Explanation
Population density is a measurement of population per unit area, typically expressed as the number of persons per square kilometer. The Census of India 2011 provides the official data regarding the spatial distribution and density of the population across states and Union Territories.
Analysis:
- Arunachal Pradesh: It recorded the lowest population density among all states in India, with only 17 persons per sq. km.
- Mizoram: It recorded a population density of 52 persons per sq. km.
- Sikkim: While Sikkim is the state with the lowest total population, its density is higher than Arunachal Pradesh, standing at 86 persons per sq. km.
- Jammu & Kashmir: According to the 2011 Census (prior to the reorganization into UTs), the density was 124 persons per sq. km.
Key Takeaway:
As per Census 2011, Arunachal Pradesh has the lowest population density (17 persons/sq. km), whereas Bihar has the highest population density among states (1106 persons/sq. km).