The correct answer is: Office of the Registrar General and Census Commissioner.
The Office of the Registrar General and Census Commissioner (ORGC) is the nodal agency for conducting the Census in India. It is a statutory body under the Ministry of Home Affairs. The ORGC is responsible for planning, organizing, and conducting the Census of India, which is held every 10 years. The Census provides a comprehensive and reliable database on the population of India, which is used by the government for planning and development purposes.
The NITI Aayog is a policy think tank of the Government of India. It was set up in 2015 to replace the Planning Commission. The NITI Aayog is not responsible for conducting the Census.
The Ministry of Statistics and Programme Implementation (MoSPI) is a ministry of the Government of India. It is responsible for formulating and implementing policies and programmes for the collection, compilation, analysis, and dissemination of statistics. The MoSPI is not responsible for conducting the Census.
The Election Commission of India (ECI) is an independent constitutional body responsible for conducting elections to the Parliament of India, the legislative assemblies of the states, and the Union Territories. The ECI is not responsible for conducting the Census.