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: Medicine
The abnormal preoperative pulmonary function test in a patient with severe kyphoscoliosis includes: 
Select and explain. 
A. Reduced RV and TLC, B. Reduced FEV1/FVC., C. Reduced FEV25-75, D. Increased FRC
A: Reduced RV and TLC
Answer: A: Reduced RV and TLC 
Explanation: Answer is A (Reduced RV and TLC): Kyphoscoliosis is a restrictive lung disease. There is decrease in residual volume and total lung capacity. FEV1 and FVC are propoionately decreased. Hence the ratio of FEV1 to FVC remains normal or is increased. The forced expiratory flow rate (FEF) is normal. Functional residual capacity (FRC) is decreased.