You are presented with the quiz "What can cause a short-term cooling of the Earth's climate?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "the movement of tectonic plates causes volcanic eruptions" and "volcanic eruptions can cause short-term cooling of the Earth's climate". 

So, what's the best answer to the question?


 

   The movement of tectonic plates.        