What fills the space between the cornea and the iris?

The space between the cornea and the iris is filled with aqueous humor, a clear fluid that is produced by the ciliary body. This fluid is essential for maintaining intraocular pressure, providing nutrients to the avascular structures of the eye, such as the lens and cornea, and removing metabolic wastes. The aqueous humor circulates through the anterior chamber of the eye, located between the cornea and the iris, helping to maintain the shape and stability of the eye.

Other options do not correctly describe the substance that fills this specific space. Vitreous humor is found in the larger space behind the lens, known as the vitreous cavity. Chamber fluid and subretinal fluid refer to different contexts within ocular anatomy and physiology, thus further validating that aqueous humor is the correct answer for the fluid filling the space between the cornea and the iris.