Which of the following statement/s regarding literacy in India is/are correct?
1. A person who can only read but cannot write is not defined literate
2. Children below 7 years of age are not taken into consideration even if they are able to read and write
3. For the purpose of the census, a person is deemed literate if he or she can read and write with understanding in any of the 22 languages mentioned in the Eighth Schedule of the constitution
4. The fact that a district has attained hundred percent literacy does not mean that the entire population in the district is literate