Hint: The blind spot is the area on the retina without receptors that respond to light. So if an image is fallen on that region will not be seen. the optic nerve in Blind Spot exits the eye on its path to the brain.
Let’s discuss the options and find out the correct answer
A. Fovea -The fovea is the region where maximum no. of cone cells exist.It is responsible for sharp central vision which is necessary in humans for reading, driving and in any other activity.
B.Iris-Iris is the part of the eye which regulates the size of the eye and controls the amount of light. The coloured part of the eye.Pigments in the iris are made of melanin.Pigments helps in creating eye colour .
C.Blind spot-It is that part of the vertebrate eye, where the optic nerve passes out of the retina, which is known as blind spot. It is that part of the retina which does not contain receptors that responds to light .This option is correct.
D.Optic chiasm-Photoreceptors are absent from this region. The optic nerve is the nerve which works to carry the impulse from the photoreceptors to the optic lobes of the brain.Optic chiasm is the place where the optic lobes overlap.
Hence option c is correct.
Note: Once the optic nerve is damaged it cannot be repaired since the damage is irrecoverable. It is composed of nerve fibers that do not have the ability to reconstruct on their own. The nerve fibers, if damaged, cannot recover on their own.