You are presented with the question "What kind of circulatory system do fish have?" and the following answer choices: 
- open
 - solid
 - closed
 - three
 - stagnant
 - kinetic
 - complex
 - gills

Now knowing that chordates have a complete digestive system and a closed circulatory system and chordates Chordates Chordates include fish, amphibians, reptiles, birds, and mammals, choose the best answer.


 

   closed      