This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Decrease in diffusion is diagnosed by: 
Select and explain. 
A. DLCO, B. Spirometer, C. Both, D. None
A: DLCO
Answer: A: DLCO 
Explanation: DLCO Stands for diffusion capacity for carbon monoxide It is used to estimate diffusion capacity of the lungs