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: Orthopaedics
10 year old boy complaints of pain in right arm near the shoulder, x-ray shows expansile lytic lesion in upper third of humerus, what is the likely diagnosis. 
Select and explain. 
A. Aneurysmal Bone cyst, B. Simple bone cyst, C. Giant cell tumor, D. Osteosarcoma
B: Simple bone cyst
Answer: B: Simple bone cyst 
Explanation: None