<prompt> Which of the following is a pulsatile tumour?OsteosarcomaChondrosarcomaEwings sarcomaOsteoclastoma  <response>: Both osteoclastoma and telangiectatic osteosarcoma can present as pulsatile tumours. However, the best answer here is osteoclastoma, because, telangiectatic osteosarcoma is a less common variant of osteogenic sarcoma. Further, telangiectatic osteosarcoma can be pulsatile in very rare cases. So, the overall frequency is very less.Pulsatile bone tumorsGiant cell tumor osteoclastomaTelengiectatic osteosarcomaAngiosarcomaangioendothelioma of boneAneurysmal bone cystSecondaries from thyroid carcinoma and hypernephroma renal cell carcinoma. 