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': 'A patient presents with respiratory distress, hypotension and dilated bulging neck veins after chest trauma, most likely cause is- \nSelect and explain. \nA. Hemothorax, B. Tension Pneumothorax, C. Cardiac tamponade, D. Flail chest', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]