You are presented with the question "What lack respiratory and excretory systems?" and the following answer choices: 
- deuterostomes
 - barnacles
 - cigarettes
 - graptolites
 - fish
 - humans
 - kalenchoes
 - birds

Now knowing that echinoderms lack respiratory and excretory systems and all echinoderms are deuterostomes , choose the best answer.


 

 deuterostomes        