This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: JIPMER 2018, Subject name: Orthopaedics
Ewing's sarcoma peak incidence: 
Select and explain. 
A. 1st decade, B. 2nd decade, C. 3rd decade, D. 4th decade
B: 2nd decade
Answer: B: 2nd decade 
Explanation: The most common bone tumor of 1st decade is Ewing's sarcoma. The most common bone tumor of 2nd decade is osteosarcoma. Both osteosarcoma and Ewing's sarcoma peak in 2nd decade (10-20 years of age).