Detailed Solution:
The correct answer is “2 Only”.
1) According to the 2011 population census, the literacy rate in Uttar Pradesh is 67.68 per cent.
2) According to Census 2011, the population of Uttar Pradesh was 19.98 Crores. The population density of the state is 829 persons per square kilometre.
3) Prayagraj district, also known as Allahabad district, is the most populous district in the Indian state of Uttar Pradesh.
4) The Sitapur district of Uttar Pradesh is having a maximum SC population.