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 am hesitating between 4 options to answer the following question, which option should I choose?
Question: When stratospheric ozone levels are reduced, the amount of ultraviolet radiation hitting Earth increases. Ozone depletion is most often caused
Possibilities:
- 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.

when fluorocarbons are released into the atmosphere.