This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumors, Subject name: Orthopaedics
Which of the following is associated with poor prognosis in Ewings sarcoma? 
Select and explain. 
A. B2 microglobulin, B. Fever, C. Thrombocytosis, D. Young age
B: Fever
Answer: B: Fever 
Explanation: IMAGE SHOWS PROGNOSTIC FACTORS OF EWINGS SARCOMA REF : MAHESWARI 9TH ED