You are presented with the quiz "What kind of circulatory system do fish have?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "chordates have a complete digestive system and a closed circulatory system" and "chordates Chordates Chordates include fish, amphibians, reptiles, birds, and mammals". 

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


 

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