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
In a young boy, x-ray of the upper end of the tibia shows a lytic lesion. The least likely diagnosis is- 
Select and explain. 
A. Giant cell tumor, B. Osteosarcoma, C. Solitary bone cyst, D. Tuberculosis
A: Giant cell tumor
Answer: A: Giant cell tumor 
Explanation: Giant cell tumour occurs between 20-40 years (not in a young child)
Telangiectatic type of osteosarcoma, solitary bone cyst and tuberculosis can cause an osteolytic lesion in a child.