Question: What lacks respiratory and excretory systems?
Options:
- (A) the Sun
- (B) insects
- (C) starfish
- (D) barnacles
- (E) ferns
- (F) water
- (G) Conifers
- (H) humans
Let's be accurate as possible and think step-by-step.
Echinoderms lack respiratory and excretory systems. Echinoderms are represented by the starfish. Starfish lack respiratory and excretory systems.
The answer: (C).