The answer would logically be A.
An oil spill covering an entire ocean has nothing to do with politics.
Nor does C.
B doesn't really contribute much to the question at hand. Sure, he's a politician, but who cares about the large glasses or big ears?
The answer is C.
As a science website says, "Scientists think they know why the Ancestral Puebloans disappeared. The primary culprit, studies suggest, was a megadrought that would have made it impossible to grow enough food to feed the tens of thousands of people living in the region."
If you didn't know, drought represents the lack of rain.
