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': 'Following is true about cystic Fibrosis \nSelect and explain. \nA. Nasal polyposis is absent, B. Sweat chloride levels > 30 mmol / L is diagnostic, C. Staphylococcus is most common pathogen  causing  infection in cystic fibrosis in adults., D. Chromosome - 7 genetic defect', 'role': 'user'}, {'content': 'Answer: D \nExplanation: In adults pseudomonas is most common arganism causing infection in cystic fibrosis adult patients.\nSweat chloride levels > 60 mmol / L is diagnostic.\nNasal polyps is present.', 'role': 'assistant'}]