Explanation:

The European Space Agency Copernicus Sentinel-5P satellite made the recordings of ozone hole. The large ozone hole over Antarctica is one of the biggest on record, roughly three times the size of Brazil.

• Statement I is correct: Most of the ozone depletion happens over Antarctica, in the south polar stratosphere, the conditions become most favourable for ozone destruction. The primary chemicals involved in ozone depletion are chlorofluorocarbons (CFCs), halons, and carbon tetrachloride.

• Statement II is correct: The size of the ozone hole over Antarctica fluctuates each year, opening each year in August and closing again in November or December. The key factor leading to ozone hole formation is the presence of stratospheric clouds and the lack of atmospheric mixing between the south polar latitudes and air from elsewhere during this period.

• Statement-II is the correct explanation for Statement-I: The ozone hole opens up because of the rotation of the Earth causing special winds over the closed landmass of Antarctica. The winds create a mini climate, creating a shield over Antarctica preventing it from mixing with surrounding air. When the winds die down, the hole closes.

Hence option 1st is correct.