Physiology Normal diffusion of CO2 at rest- A 20-25 mL/min/mm Hg B 50-100 mL/min/mm Hg C 100-200 mL/min/mm Hg D 300-400 mL/min/mm Hg 💡 Explanation Normal diffusion of CO2 at rest- ✓ Correct Answer: D. 300-400 mL/min/mm Hg