About the eyeball wall, which of the following descriptions are correct?
选项：

A:The cornea occupies the anterior 1/6 of the fibrous tunic.
B:The sclera is a transparent (透明的) and non-vascular structure.
C:In the center of the iris is the pupil.
D:The ciliary body is a part of the vascular tunic and has the function to secrete the aqueous humor (
E:The retina can be divided into two parts: ciliary part and optic part.