In eye donation,which one of the following parts of the donor's eye is utilized?

$X -$ Rod cells' function is twilight (scotopic) vision.
$Y -$ Cone cells' function is daylight (photopic) vision.

Which of the following statements is correct regarding the pupil of the human eye?
$(I)$. It is the aperture surrounded by the iris.
$(II)$. The diameter of the pupil is regulated by the muscle fibres of the iris.
$(III)$. It is a transparent crystalline structure attached to the ciliary body.
The correct option is:

The muscles surrounding the pupil of a rabbit's eye are:

The fovea centralis of the retina perceives:

Which one of the following statements is not correct?