This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breast Cancer - Prognosis and Follow-Up, Subject name: Surgery
[{'content': 'Brain metastasis are common among which of the following malignancy \nSelect and explain. \nA. Breast, B. Testis, C. Thyroid, D. Tongue', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans) a (breast) Ref: Sabiston's textbook of surgery 18th editionMetastatic brain tumors are the most common tumors of the brain.They out number primary brain tumors by 10 to 1The most common primary sites are lung (50%), breast cancer (15%-20%), unknown pri mary cancer (10%-15%), melanoma (10%)Metastases to the brain are multiple in more than 70% of casesMRI with gadolinium enhancement is the diagnostic study of choice for metastases", 'role': 'assistant'}]