Echinoderms lack a centralized nervous system, and echinoderms are represented by the starfish. Given these facts, what is something missing in starfish among the following options:
- the body's largest organ
 - centralized nervous system
 - characteristics
 - layers of fat
 - permineralization
 - biological diversity
 - kinetic energy
 - A compound that donates proton


 

  centralized nervous system       