Physiology A spirometry curve of a patient has been provided below. Calculate the FEV1/FVC ratio from the curve: A 60-69% B 70-79% C 80-89% D 90-99% 💡 Explanation A spirometry curve of a patient has been provided below. Calculate the FEV1/FVC ratio from the curve: ✓ Correct Answer: C. 80-89%