You are presented with the quiz "These belong to the class of creature that were the first true tetrapods:" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "amphibians are the first true tetrapods, or vertebrates with four limbs" and "bullfrogs eat other amphibians". 

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


 

    bullfrogs       