Detailed Solution:
The correct answer is “Copenhagen”.
The first World Summit on Social Development, under the aegis of UNESCO (United Nations Educational, Scientific and Cultural Organization), was held in Copenhagen, Denmark.
Therefore, the correct answer is (d) Copenhagen.
The summit took place from 6 to 12 March 1995 and aimed to address various social development issues and promote strategies for eradicating poverty, reducing inequality, and enhancing social well-being at a global level.