QQuestion
Cornea, Choroid, Lens, Aqueous humour, Iris, Vitreous humour — how many of these are refractory media of the eyeball?
(a) 3
(b) 4
(c) 5
(d) 6
✓Answer
(b) 4
Explanation
The refractory media of the human eye are the transparent structures that help to refract (bend) light rays to focus them on the retina. These include the cornea, aqueous humour, lens, and vitreous humour. The cornea forms the main refractive surface, while the other three media fine‑tune the focus of light. The choroid and iris are not refracting media; they provide nourishment and regulate light entry, respectively.
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