You are presented with the quiz "When electricity flows to a light bulb, the energy it uses becomes what?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "when electricity flows to a light bulb , the light bulb will turn on" and "most of the energy a light bulb uses turns into heat". 

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


 

     heat      