Which sequence correctly describes the flow of aqueous humor?

• A. Produced by ciliary body; flows through pupil to the anterior chamber; exits via canal of Schlemm
• B. Produced in the cornea; flows to the posterior chamber; drained by lacrimal duct
• C. Produced by the retina; flows to the vitreous; drained by the optic nerve
• D. Produced by the sclera; flows into the choroid; exits via the cornea

Answer: (A)

Aqueous humor is produced by the ciliary body and flows from there into the posterior chamber, then through the pupil into the anterior chamber. From the anterior chamber, it drains primarily through the trabecular meshwork into Schlemm’s canal and onward to the venous system. This sequence—production by the ciliary body, passage through the pupil into the anterior chamber, and drainage via Schlemm’s canal—is the correct description.

The other ideas don’t fit the reality: production by the cornea isn’t how aqueous is formed; the retina and vitreous relate to the eye’s posterior structures, not the aqueous system; tear drainage is through the lacrimal duct, not the aqueous outflow; and the sclera or flow directly into the cornea aren’t the normal drainage paths for aqueous humor.