30 points please help a girl out! 

A political action group that wants to overturn the Montreal Protocol monitors stratospheric ozone across the South Pole over a 10-year period. They compare changes in the ozone layer to increases in the average global temperature and find no correlation. Because of this, they claim that ozone layer depletion is a myth. What is the major flaw in their reasoning?

a. Global warming is not observable at the South Pole.
b. Only tropospheric ozone will correlate to global warming.
c. The loss of stratospheric ozone is not connected to global warming.
d. The effects of the Montreal Protocol will not be fully realized until 2050.
e. Ten years is too short a time period for meaningful data to be acquired.