Echinoderms lack a centralized nervous system.
Echinoderms are represented by the starfish.
Starfish lack a centralized nervous system.
What is something missing in starfish?

A) the body's largest organ
B) centralized nervous system
C) characteristics
D) layers of fat
E) permineralization
F) biological diversity
G) kinetic energy
H) A compound that donates proton