<prompt> EV1FVC is reduced in case ofPleural effusionLung fibrosisAsthmaAll of the above  <response>: Answer is C Asthma: Reduction in FEVIFVC is the hallmark of obstructive lung diseases. Amongst the options provided, Asthma is the only obstructive disease and thus the answer of choice. The hallmark in obstructive pattern of disease is a decrease in expiratory flow rates. Decrease in Forced Expiratory flow rate FEF25_75 and FEVIFVC are characteristic. 