Which of the following malignancy responds best to radiotherapy?

Radiosensitive tumours are ones which responds rapidly after radiotherapy. This doesn't mean that they are radio-curable. Radio-curability depends on each tumours propensity to metastasis. Localised tumours are more radiocurable even when they are not radiosensitive. E.g. laryngial Ca, Basal Cell Ca. The most radiosensitive tumours are malignant lymphomas, seminomas, medulloblastoma, neuroblastoma, Wilm's tumour, early cervical carcinoma, vaginal carcinoma and most head and neck tumours. Ref: Handbook of Community Cancer Care By Mark N. Gaze, Isobel M. Wilson, Pages 61-62; Walter and Miller's Textbook of Radiotherapy By C. K. Bomford, I. H. Kunkler, Joseph Walter; Harrisons Internal Medicine, 18th Edition, Chapter 39, Pages 87, 94.