Echinoderms lack respiratory and excretory systems, and starfish and sea urchins are also echinoderms. Given these facts, what is an example of an animal that lacks a respiratory and excretory system among the following options:
- Dog
 - Human
 - alpacas
 - cacti
 - Starfish
 - Leeuwenhoek
 - Elephants
 - cows


 

     Starfish    