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': "True about visual testing in a child –a) Visual evoked potentialb) Teller's acuity card testc) Perimetryd) Keratometry \nSelect and explain. \nA. ac, B. a, C. ad, D. ab", 'role': 'user'}, {'content': "Answer: D \nExplanation: The ordinary tests types cannot be used with young children who are easily distracted and may not know alphabets. So maturation of infant visual function has been studied by two techniques:-\n\nPattern visual evoked response/potential (VEP)\n\nPreferential looking behaviour eg. Teller or Cardiff acuity card\n\n\nOther tests include:-\n\n\nKeeler - Elliot test\xa0\xa0\nKay picture test \xa0 \xa0\xa0\nFooks symbols \xa0 \xa0 \xa0\xa0\n`E' test\xa0\xa0\xa0\xa0\xa0 \xa0\nLandolt 'C' chart\xa0\xa0\nSheridon - Gardiner\nHOTV\xa0\nOptokinetic nystagmus\nPhotostress test\nSTYCAR (sight testing for young children and retarded)", 'role': 'assistant'}]