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: Pathology
[{'content': "All of the following are examples of round cell tumours except? \nSelect and explain. \nA. Neuroblastoma, B. Non Hodgkin's lymphoma, C. Osteosarcoma, D. Ewing's sarcoma", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Small round cell tumours of childhood are:\n\nRetinoblastoma.\nNeuroblastoma.\nPNET.\nRhabdomyosarcoma.\nLymphoma.\nMedulloblastoma.\nWilms tumor.\nEwings sarcoma.', 'role': 'assistant'}]