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
Which of the following is not a small round cell tumor? 
Select and explain. 
A. Neuroblastoma, B. Retinoblastoma, C. Ewing's sarcoma, D. Hemangiosarcoma
D: Hemangiosarcoma
Answer: D: Hemangiosarcoma 
Explanation: Ans. is 'd' i.e., hemangiosarcomaSmall round blue cell tumors:* Histologically many of the malignant paediatric neoplasms are unique.* They tend to have a more primitive (embryonal) rather than pleomorphic anaplastic microscopic appearance.* Often characterized by sheets of cells with small round nuclei.* Frequently exhibit features of organogenesis specific to the site of tumour origin (therefore these tumours are frequently designated by suffix - blastoma).* Owing to their primitive histological appearance many childhood tumours have been collectively referred to as small round blue cell tumourThe differential diagnosis of small round blue cell tumours includesNeuroblastomaRhabdomyosarcomaRetinoblastomaWilms tumoursEwings sarcomaMedulloblastomaLymphomaPrimitive neuroectodermal tumoursBurkitt lymphoma