This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
[{'content': 'True about lights criteria are all except \nSelect and explain. \nA. Ratio of pleural fluid protein to serum protein if greater than 0.5 - then it is exudative pleural effusion., B. Ratio of pleural fluid LDH and serum LDH if greater that 0.5 - then its exudative pleural effusion., C. Plueral fluid LDH 2 to 3 times the upper limit of serum LDH is diagnostic of exudative pleural effusion., D. At least one of the 3 criteria is sufficient to diagnose exudative pleural effusion.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ratio of pleural fluid LDH and serum LDH if greater that 0.6\xa0- then it is exudative pleural effusion.', 'role': 'assistant'}]