<prompt> True about visual testing in a child a Visual evoked potentialb Tellers acuity card testc Perimetryd Keratometryacaadab  <response>: 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:-Pattern visual evoked responsepotential VEPPreferential looking behaviour eg. Teller or Cardiff acuity cardOther tests include:-Keeler - Elliot test Kay picture test Fooks symbols E test Landolt C chart Sheridon - GardinerHOTV Optokinetic nystagmusPhotostress testSTYCAR sight testing for young children and retarded 