The correct option is B p-ii, q-iii, r-iv, s-i
The retina is the inner layer of the eye and has three layers of cells from inside to outside: ganglion cells, bipolar cells and photoreceptor cells. The light entering the eye through the cornea passes through the aqueous humor, the lens, and the vitreous humor, where it finally forms an image on the retina.
The cornea is the anterior portion of the outer layer of the eye called the sclera. The cornea is the site in the eye where most of the refraction of light occurs. The cornea provides most of the eye's optical power or light-bending ability.
The iris is an opaque and pigmented structure which is the visible, coloured portion of the eye. Iris muscles regulate the diameter of the pupil.
The ciliary body is an extension of the iris. It contains the ciliary muscle which is responsible for the ability of accommodation of the eye lens. The ciliary muscle changes the shape of the lens when the eye focusses on a nearby object.