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
Which of the following is true for triple negative breast cancer? 
Select and explain. 
A. Aggressive tumor, B. Negative for oestrogen, progesterone, C. Good prognosis to chemotherapy, D. Tamoxifen is chemotherapeutic agent
A: Aggressive tumor
Answer: A: Aggressive tumor 
Explanation: Triple negative breast cancer has the worst prognosis.
It is negative for oestrogen receptor, progesterone receptor, HER2 receptor.