This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Orthopaedics
The most probable diagnosis of the lesion depicted in the X-ray below is (GCT) 
Select and explain. 
A. Simple bone cyst, B. Osteoma, C. Ewings tumour, D. Osteoclastoma
D: Osteoclastoma
Answer: D: Osteoclastoma 
Explanation: Osteoclastoma 98% cases are benign with potential for metastasis with female predominance Sites - Distal femur/proximal tibia, lower end of radius, proximal humerus Occurrence - 20 - 40 years Arises from epiphysis Egg shell crackling on palpation X ray finding - Soap bubble appearance HPE - mesenchymal stromal cells Treatment Lower end of femur/Upper end of tibia - Excision with turn-o-plasty Veebra - Radiation Ref: Maheshwari 6e pg 237.