This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Childhood tumors, Subject name: Pediatrics
[{'content': 'The most common site of neuroblastoma is __________ \nSelect and explain. \nA. Posterior mediastinum, B. Adrenal medulla, C. Paraveebral sympathetic chain in abdomen, D. Skull', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The most common sites of primary tumors are the adrenal gland (30%), paraveebral retroperitoneum (28%), posterior mediastinum (15%), pelvis (5%) and cervical area. Cervical neuroblastoma can present with Horner syndrome. Reference: Essential paediatrics; O.P.Ghai; Childhood Malignancies; Page no: 616', 'role': 'assistant'}]