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': 'Poorest prognosis in AML is seen in which cytogenetic abnormality - \nSelect and explain. \nA. Monosomy 7, B. No cytogenetic abnormality, C. t (15, 17), D. inv. 16', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]