You are presented with the quiz "animals in the Phylum Porifera are a source of what for many species of fish" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "sponges are a source of food for many species of fish" and "sea sponges are animals in the Phylum Porifera". 

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


 

   food        