Which of the following has the most primitive respiratory system? by Sunday | Jun 29 | Biology WAEC | 0 comments A. Rat B. Fish C. Toad D. Grasshopper E. Lizard Correct Answer: Option D – Grasshopper Users Also Read These:CHE 212 Theory Questions: Respiratory System…The respiratory organ found in the cockroach is the?In which of the following vertebrates does the skin…SS2 Biology Lesson Note on Respiratory SystemThe most efficient respiratory structure used by…