<prompt> Most common site of Ewings sarcoma -Upper end of tibiaShaft of tibiaLower end of femurShaft of femur  <response>: Ans. is d i.e., Shaft of femur Commonest siteo Ivory osteoma-Frontal sinuso Osteoid osteoma-Tibiao Admantinoma Ameloblastoma-Mandibleo Chordoma-Sacrum and cervical spineo Osteoclastoma-Lower end of femuro Ewings sarcoma-Femur diaphysis tibia diaphysiso Osteosarcoma-Distal femur 45, Proximal tibia 25o Simple bone cyst-Proximal humeruso Aneurysmal bone cyst-Bones around knee Femur, tibiao Osteochondroma-Bones around knee distal femur proximal tibiao Fibrous dysplasia-Proximal femur Tibiao Enchondroma-Phalanges of hando Multiple myeloma-Vertebraeo Metastasis-Vertebrae 