You are presented with the quiz "What effect could more active plate tectonics have on the earth?" 

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 "large volcanic eruptions can decrease (reduce)the earth's average temperature by (a) emitting particles into the stratosphere, thereby increasing the albedo". 

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


 

     Lower average temperature      