by the reversal of the magnetic field of Earth. when fluorocarbons are released into the atmosphere. when electromagnetic waves from the Sun increase. by abrupt changes in weather and climate patterns.
I gave my students this multiple choice question: When stratospheric ozone levels are reduced, the amount of ultraviolet radiation hitting Earth increases. Ozone depletion is most often caused

Only one answer is correct among these 4 choices:
- by the reversal of the magnetic field of Earth.
- when fluorocarbons are released into the atmosphere.
- when electromagnetic waves from the Sun increase.
- by abrupt changes in weather and climate patterns.

Could you tell me which one is correct?

when fluorocarbons are released into the atmosphere.