Final answer:
In the case of amblyopia, your question pertains to the retina, which is responsible for receiving the light information and beginning the visual processing. The retina's role is vital in amblyopia as improper development of the neural pathways between the retina and the brain can lead to this condition.
Step-by-step explanation:
Amblyopia, often referred to as "lazy eye," is a visual development disorder where an eye fails to achieve normal visual acuity, even with prescription eyewear. When explaining amblyopia to a patient, the focus should be on structures involved in the development of visual acuity. One of the critical structures involved in this condition is the retina.
The retina is the innermost layer of the eye and contains the nervous tissue responsible for photoreception. It is precisely the part of the eye where light is focused and where visual processing begins. The retina has specialized photoreceptor cells, called rods and cones, that detect light and color, respectively. In amblyopia, the affected eye's neural pathway to the brain doesn't develop properly, which can happen if the image isn't focused on the retina as it should be during critical periods of childhood development.
Considering other options from the question, the pupil regulates the amount of light entering the eye, the sclera is the white part of the eye providing structural support and protection, and orbital muscles control eye movement. However, they are less relevant when directly addressing the structure involved in the pathology of amblyopia.