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: Pathology
[{'content': 'Caissons disease is caused by \nSelect and explain. \nA. Amniotic fluid embolism, B. Hyper coagulability, C. Air or gas embolism, D. Tumour embolism', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]