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: Biochemistry
[{'content': "Refsum's disease is due to deficiency of which of the following enzyme? \nSelect and explain. \nA. Malonate dehydrogenase, B. Thiophorase, C. Succinate thiokinase, D. Phytanic alpha oxidase", 'role': 'user'}, {'content': 'Answer: D \nExplanation: Phytanic alpha oxidase\xa0\n\nRefsum disease is caused by a deficiency of phytanic acid α -hydroxylase (α -oxidase) which is required for a-oxidation of methylated fatty acids, phytanic acid.', 'role': 'assistant'}]