<prompt> Snellens chart is used to test?Visual acuityContrast sensitivityVisual fieldsColour vision  <response>: Ans. is a i.e., Visual acuity Visual acuity of a eye is its ability to discriminate between two points, i.e. measure of the spatial resolution of the eye. Ones visual acuity is an indication of the clarity or clearness of ones vision. It is a measurement of how well a person sees. Visual acuity is most commonly measured by Snellens visual acuity chart. 