<prompt> Malignant bone tumors are all except:OsteosarcomaGaint cell tumor OsteoclastomaAneurysmal bone cystChondrosarcoma  <response>: Ans: C Aneurysmal bone cyst Aneurysmal hone cysts are locally destructive, blood-filled reactive lesions of bone and are not considered to be true neoplasmsApey; benign neoplasm-Maheshwari. Any bone may be involved, but the most common locations include the proximal humerus, distal femur, proximal tibia, and spine-Apley 8th180-81. Maheshwari 3rd227Giant cell tumors are benign, indeterminate malignant- Maheshwari 3rd 214Table Robbins 7thfl292: Classification of Primary Tumors In- volving BonesHistologic TypeBenignMalignantHematopoietic 40 MyelomaMalignant lymphomaChondrogenic 22OsteochondromaChondrosarcomaChondromaDedifferentiated cho- drosarcomaChondroblastomaMesenchymal chon- drosarcomaChondromyxoid fibroma Osteogenic 19Osteoid osteoma OsteoblastomaOsteosarcomaUnknown origin 10Giant cell tumorEwing tumorGiant cell tumor AdamantinomaHistiocytic originFibrous histiocytomaMalignant fibrous histiocytomaFibrogenicMetaphyseal fibrous defect fibromaDesmoplastic fibromaFibrosarcomaNotochordal ChordomaVascularHemangiomaHemangioendothelioma HemangiopericytomaLipogenic NeurogenicLipoma NeurilemmomaLiposarcoma 