This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Retina, Subject name: Ophthalmology
[{'content': "Retinitis pigmentosa is a feature of all except: \nSelect and explain. \nA. Refsum's disease, B. Hallervorden-Spatz disease, C. NARP, D. Abetalipoproteinemia", 'role': 'user'}, {'content': "Answer: B \nExplanation: Now Hallervorden Spatz doesn't have RP as a feature. Remember RP associations by mnemonic LUCHR. *Lawrence moon Beidel syndrome *Usher *Cockayne *Hallgren *Refsum Other associations: NARP, Abetalipoproteinemia", 'role': 'assistant'}]