You are presented with the quiz "what fossils have to be found in a place to signify the place used to be covered by water?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "if fossils of a water animal or plant are found in a place then that place used to be covered by water in the past" and "barnacles are animals that live in the water". 

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


 

     barnacles      