Which one of the following is not the central feature of Article 343 of Constitution of India?
1.Hindi of Devnagri script shall be national language of the Union
2.The official language of the Union shall be Hindi in Devnagri script
3.English language shall continue to be used for official purposes within States
4.If two or more states agree,Hindi should be the official language of communication between the states
Select the correct answer using the codes below