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:List FOUR characteristics of respiratory surfaces. -…CHE 212 Theory Questions: Respiratory System…Write the respiratory structure of amoeba, five day…In birds, loss of appetite, respiratory difficulties…The respiratory organ found in the cockroach is the?