Match List-I with List- II  with respect  to human eye. 

	List - I		List - II
(A)	Fovea	(I)	Visible coloured portion  of eye that regulates diameter of pupil.
(B)	Iris	(II)	External layer of eye formed of dense connective tissue.
(C)	Blind spot	(III)	Point of greatest visual acuity of resolution
(D)	Sclera	(IV)	Point where  optic nerve leaves the eyeball and photoreceptor cells are absent.

Choose the correct answer  from the  options below 

	(A)	(B)	(C)	(D)
1.	II	I	III	IV
2.	III	I	IV	II
3.	IV	III	II	I
4.	I	IV	III	II

A-III, B-I, C-IV, D-II

A. The fovea is a small, central area in the retina of the eye. It is responsible for the highest visual acuity and resolution in the visual fi eld. The fovea contains a high concentration of cone cells, which are photoreceptor cells responsible for
colour vision and visual detail. 

B. The iris is the coloured part of the eye that surrounds the pupil. It is composed of muscles that control the size of the
pupil, regulating the amount of light entering the eye. The iris adjusts the diameter of the pupil in response to varying lighting conditions, allowing for the appropriate amount of light to reach the retina.

C. The blind spot (optic disc) is the area on the retina where the optic nerve exits the eye. It is devoid of photoreceptor cells, resulting in a lack of visual perception in that specific spot. 

D. The sclera is the tough, outer layer of the eye that maintains the shape of the eye and provides protection. It is composed of dense connective tissue, giving the eye its white appearance. The sclera covers most of the eyeball, except for the front portion, which is covered by the transparent cornea.