Nutrients Are Delivered and Waste Products Are Carried Away from the Cells

Nutrients are delivered and waste products are carried away from the cells of the posteriorsegment of the eye by blood vessels. However, the cells in the cornea and lens (in the anterior segment) are avascular. Which is the best explanation for how these cells are maintained?

A) These cells, like the cells of the corneal layer of the integument are not living cells.
B) The aqueous humor is continuously replenished and flows from the ciliary process to drain in the scleral venous sinus.
C) The metabolic activity of these cells is very low. They produce little waste and need few nutrients.
D) The nutrients and waste products of the anterior segment diffuse into and through the vitreous humor of the posterior segment.