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
CD-99 is the marker for: 
Select and explain. 
A. Ewing's sarcoma, B. SLL, C. Dermatofibroma protruberans, D. Malignant histiocytic fibroma
A: Ewing's sarcoma
Answer: A: Ewing's sarcoma 
Explanation: . Ewing&;s sarcoma