You are presented with the quiz "The moon's gravitational pull on Earth 's oceans causes the vertical movement of what?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "the gravitational pull of the Moon on Earth 's oceans causes the tides" and "tides A tide is vertical movement of water". 

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


 

        water   