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: Surgery
Most common site of Ewing's sarcoma ? 
Select and explain. 
A. Upper end of tibia, B. Shaft of tibia, C. Lower end of femur, D. Shaft of femur
D: Shaft of femur
Answer: D: Shaft of femur 
Explanation: Ans. is 'd' i.e., Shaft of femur Commonest site Ivory osteoma - Frontal sinus Osteoid osteoma - Tibia Admantinoma (Ameloblastoma) - Mandible Chordoma - Sacrum and cervical spine Osteoclastoma - Lower end of femur Ewing's sarcoma - Femur diaphysis > tibia diaphysis Osteosarcoma - Distal femur (45%), Proximal tibia (25%) Simple bone cyst - Proximal humerus Aneurysmal bone cyst - Bones around knee (Femur, tibia) Osteochondroma - Bones around knee (distal femur > proximal tibia) Fibrous dysplasia - Proximal femur > Tibia Enchondroma - Phalanges of hand Multiple myeloma - Veebrae Metastasis - Veebrae