<prompt> Normal level of visual acuity is attained at which age6 months1 year3 years6 years  <response>: In clinical practice, measurement of the threshold of discrimination of two spatially-separated targets a function of the fovea centralis is termed visual acuity Visual acuity recorded by Snellen;s test cha is a measure of the form sense Reference : A K KHURANA Comorehensive Ophtalmology edition 4,page-16 