The correct option is(3) 16th September
Explanation:
'World Ozone Day' is celebrated on 16th September to control O3 depletion. Ozone layer is a fragile shield of gas that protects earth from harmful UV-rays.
On 21st Aprili the Civil Service Day and National Yellow Bat Day is ceiebrated. 5th June of every year is celebrated as World Environment Day.
Earth Day is an annual event, celebrated on 22nd April of every year.
