<prompt> All the following are true about Chronic Obstructive lung disease except:Decreased FeV1Decreased MEFRIncreased RVDecreased diffusion capacity  <response>: Answer is D Decreased diffusing capacity : Diffusion capacity is not affected in Obstructive lung diseases 9acute or chronic. It is decreased in restrictive lung disease. Decreased in expiratory flow rate is a hallmark of obstructive lung disease. i,MEFR Residual volume is increased FEVIFVC is decreased FEV1 is also decreased. FEV1forced expiratory volume in one second; FVCForced Vital Capacity; FEF25_75Forced Expiratory Flow at 2575 vital capacity; TLC Total Lung Capacity; DLCODiffusion Capacity of the Lung for Carbon monoxide. 