Some time ago formation of polar stratospheric clouds was reported over Antarctica. Why were these formed? What happens when such clouds break up by warmth of sunlight?

Options

1. APolar stratospheric clouds form due to volcanic emissions and break up into rain.
2. BPolar stratospheric clouds form as a result of increased water and dissipate into the atmosphere.
3. CPolar stratospheric clouds form due to the extreme cold in polar regions and release ozone-depleting substance
4. DPolar stratospheric clouds form from industrial pollution and dissipate, leading to improved air quality.