Final answer:
Light must be focused directly on the retina for maximum visual acuity to occur.
Step-by-step explanation:
The correct answer is Retina.
In order for maximum visual acuity to occur, light must be focused directly on the retina. The retina is a layer of light-sensitive cells at the back of the eye that contains specialized photoreceptor cells called rods and cones. These cells detect light and send signals to the brain through the optic nerve.
The fovea, a small indentation in the retina, has the greatest density of cones and provides the greatest acuity (sharpness) in the visual field.