Most important factor determining convergence of light rays on the retina is: (A) Length of eyeball, (B) Refractive index of cornea, (C) Dioptre power of lens, (D) Physical state of vitreous
Answer is B. refracting structures with their refractive indices given in parentheses-cornea (1.37), the aqueous humour (1.33), the crystalline lens (1.42), and the vitreous humour (1.33).
The total dioptric power of the eye is about +60 D out of which about +44 D is contributed by the cornea and +16 D by the crystalline lens.