The correct answer is Ministry of Home Affairs. Explanation & Key Takeaways: • The Office of the Registrar General and Census Commissioner (ORGI) was established in 1961 by the Government of India to provide a permanent foundation for the census organization. • It operates under the administrative control of the Ministry of Home Affairs (MHA), which oversees the security and internal policy of the country. • The organization is headed by the Registrar General and Census Commissioner of India, who is typically an officer of the rank of Joint Secretary or above from the Indian Administrative Service (IAS). • The primary responsibility of this office is to conduct the decennial Population Census, which is authorized under the Census Act, 1948. • It is also responsible for the implementation of the Registration of Births and Deaths Act, 1969, which manages the Civil Registration System (CRS) across India. • The office plays a critical role in the maintenance of the National Population Register (NPR) under the Citizenship Act, 1955 and the Linguistic Survey of India. Related Concepts: • Ministry of Statistics and Programme Implementation (MoSPI): • MoSPI is the nodal agency for the planned development of the statistical system in the country and manages the National Statistical Office (NSO). • While it conducts major surveys like the Periodic Labour Force Survey (PLFS) and computes the Consumer Price Index (CPI), it is not responsible for the population census. • Constitutional and Historical Context: • The Census is a Union Subject listed under Entry 69 of the Seventh Schedule of the Constitution of India. • The first census in India was conducted in 1872 under Lord Mayo, but the first synchronous (complete) census took place in 1881 under Lord Ripon. • The Census Commissioner was a temporary post until the office was made permanent in 1961.