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: Surgery
Opsomyoclonus is encountered as C/F of - 
Select and explain. 
A. Meningioma, B. Neuroblastoma, C. Neurofibromatosis, D. Excision
B: Neuroblastoma
Answer: B: Neuroblastoma 
Explanation: "At least 50% of children with opsoclonus-myoclonus have an underlying neuroblastoma." - Harrison
Opsoclonus-Myoclonus Syndrome 

Opsoclonus is a disorder of eye movement characterized by involuntary, chaotic saccades that occur in all directions of gaze; it is frequently associated with myoclonus and ataxia.

Causes of Opsoclonus-myoclonus 

Idiopathic
Cancer-related (paraneoplastic)


Cancers associated with opsoclonus-myoclonus are usually lung and breast cancers in adults and neuroblastoma in children.