This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardio thoracic surgery  , Subject name: Surgery
Adult respiratory distress syndrome is defined by all except: 
Select and explain. 
A. PCWP > 18 mmHg, B. PaO2/FiO2 < 200, C. Diffuse bilateral air space edema on Chest X-Ray, D. All of the above
A: PCWP > 18 mmHg
Answer: A: PCWP > 18 mmHg 
Explanation: Diagnostic Criteria Acute Lung Injury (ALI) ARDS PaO2/FiO2 </= 300 mmHg </= 200 mmHg Onset Acute Acute Chest X-Ray Bilateral alveolar or interstitial infiltrates Bilateral alveolar or interstitial infiltrates Absence of Left Atrial Hypeension PCWP </= 18 mmHg No Clinical evidence of increased left atrial pressure PCWP </= 18 mmHg No clinical evidence of increased left atrial pressure Ref: Harrison&;s 19th edition Pgno: 1736