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: Ophthalmology
[{'content': 'Optokinetic nystagmus is due to defect in \nSelect and explain. \nA. Frontal lobe, B. Occipital lobe, C. Temporal lobe, D. Parietal lobe', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Optokinetic nystagmus constitutes of saccadic and pursuit movements.\nDefect in OKN indicates parietal lobe lesion.', 'role': 'assistant'}]