This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Medicine
The abnormal preoperative pulmonary function test in a patient with severe kyphoscoliosis includes 
Select and explain. 
A. Normal RV and decreasd TLC, B. Reduced FEV1/ FVC, C. Reduced FEV 25-75, D. Increased FRC
A: Normal RV and decreasd TLC
Answer: A: Normal RV and decreasd TLC 
Explanation: In severe kyphoscoliosis RV is normal TLC decreased FRC decreased/normal FVC decreases