Answer : 2. "1968"
Explanation :

1. In the meeting of the National Unity Council held in the year 1968, its objective was announced which is as follows - “Our Constitution is based on Common Citizenship, Unity in Diversity, Freedom of Religions, Secularism.” ), equality, political-socio-economic justice and brotherhood among all communities.”

2. The National Unity Council is committed to adhering to these constitutional values.

3. Its objective is to find solutions to overcome the problems of communalism, casteism and regionalism.