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: Orthopaedics
[{'content': 'Expansile lytic osseous metastases are characteristics of primary malignancy of - \nSelect and explain. \nA. Kidney, B. Bronchus, C. Breast, D. Prostate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Renal (kidney) carcinoma\xa0\xa0\xa0\xa0\xa0\xa0 →\xa0\xa0\xa0\xa0\xa0\xa0 Osteolytic bone metastasis.\nBreast and lung (bronchus)\xa0\xa0\xa0\xa0 →\xa0\xa0\xa0\xa0\xa0\xa0 Mixed osteolytic - Osteoblastic\nProstate carcinoma\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0→\xa0\xa0\xa0\xa0\xa0\xa0 Osteoblastic metastasis', 'role': 'assistant'}]