This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Imaging of Interstitial Lung Disease, Subject name: Radiology
[{'content': 'A breast cancer patient presents with difficulty on breathing. CXR shows? \nSelect and explain. \nA. Canon ball metastasis, B. Pneumothorax, C. Pulmonary artery hypertension, D. Interstitial lung disease', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) Canon ball metastasis.', 'role': 'assistant'}]