You are presented with the question "What lacks respiratory and excretory systems?" and the following answer choices: 
- the Sun
 - insects
 - starfish
 - barnacles
 - ferns
 - water
 - Conifers
 - humans

Now knowing that echinoderms lack respiratory and excretory systems and echinoderms are represented by the starfish, choose the best answer.


 

   starfish      