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': 'Right hemithorax with right side shift of mediastinum is due to - \nSelect and explain. \nA. Collapse of Rt lung, B. Right side hemothorax, C. Hydrothorax Rt sided, D. Bronchiectasis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]