First Monday of October is observed every year as internationally?

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A. Health Day
B. Habitat Day 
C. Society Day
D. Education Day

Explanation:

In 1985 the United Nations designated the first Monday of October every year as World Habitat Day. The idea is to reflect on the state of our towns and cities and the basic right of all to adequate shelter. It is also intended to remind the world of its collective responsibility for the future of the human habitat.