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: Surgery
[{'content': 'Which of the following is true for triple negative breast cancer? \nSelect and explain. \nA. Aggressive tumor, B. Negative for oestrogen, progesterone, C. Good prognosis to chemotherapy, D. Tamoxifen is chemotherapeutic agent', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Triple negative breast cancer has the worst prognosis.\nIt is negative for oestrogen receptor, progesterone receptor, HER2 receptor.', 'role': 'assistant'}]