This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
A spirometry curve of a patient has been provided below. Calculate the FEV1/FVC ratio from the curve: 
Select and explain. 
A. 60-69%, B. 70-79%, C. 80-89%, D. 90-99%
C: 80-89%
Answer: C: 80-89% 
Explanation: Answer- C. 80-89%