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: Pathology
[{'content': 'The gene for Breast Cancer (BRCA) is present on chromosome: \nSelect and explain. \nA. 21, B. 17, C. 15, D. 9', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Women with hereditary breast-ovarian cancer susceptibility have mutation in tumor suppressor BRCA genes—\n\nBRCA-1 (located on chromosome 17q)\xa0\nBRCA-2 (located on chromosome 13q)\n\nThe risk in BRCA-1 carriers is higher compared to that in BRCA-2 carriers.\nMohan H. Textbook of pathology. Jaypee Brothers Medical Publishers; 2015. Edition 7. Page 731', 'role': 'assistant'}]