You are presented with the quiz "what lives in most terrestrial, freshwater, and marine habitats" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "mollusks live in most terrestrial, freshwater, and marine habitats" and "clams are mollusks that live in the sea or in freshwater". 

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


 

   clams        