You are presented with the quiz "What is used in order for Maglev trains to function?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "magnetism can cause objects to repel each other" and "the maglev trains are pushed and speeded up by the fact that like poles attract and unlike poles repel". 

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


 

     magnetism      