The answer is all of the above
Answer:
C, This is my answer as preventing is better than curing at the end.
1. diaphragm 2. the lungs 3a. carbon dioxide 3b. ciculatory system 4. the respitory stsem. 5. Tissues 6. capilaries 7. inhale
8. body systems 9. blood cells. 10. organs 11. the skeletal system. 12. arteries 13. oxygen 14. muscular system. 15. Alveoli 16. exhale 17. the heart. 18. veins