Concept:The first census in India was conducted in 1872 under British rule, though it was not a simultaneous count. The first synchronous census covering all regions simultaneously was held in 1881.
Explanation:The first census in India was introduced in the year 1872 during the tenure of Viceroy Lord Mayo.
It was a non‑synchronous census, meaning different regions were counted at different times.
A decade later, the first complete and simultaneous census of India was conducted on February 17, 1881.
Since 1881, the census has been carried out every ten years without interruption.
After independence in 1949, the responsibility for the census was given to the Registrar General and Census Commissioner under the Ministry of Home Affairs.
Earlier attempts include local censuses: James Prinsep in Allahabad (1824) and Banaras (1827‑28), Henry Walter in Dhaka (1830), and Fort St George (1836‑37).
However, the first official census for the whole of India is recorded as 1872.
Thus, the correct answer is 1872.
Answer:A. 1872