Cells undergo mitosis because there must be a process in which the nucleus is divided in order for there to be a successful reproduction for cells.
I would say D. small intestine
If you want an explanation, here it is
After leaving the stomach, water is absorbed mostly in the early segments of the
small intestine, the duodenum, and the jejunum. A small portion of all water absorption occurs in the stomach and the colon: the small intestine absorbs 6.5L/day, whereas the colon absorbs 1.3L/day.
<span><span>Photoreceptors
are cells</span><span><span> <span>in
the retina</span></span><span> that
begin the process of seeing. The retina is the back part of the eye that
contains the cells that respond to light. These specialized cells are called photoreceptors. They
absorb and convert light into electrical signals. These signals are sent to
other cells in the retina and ultimately through the optic nerve</span></span><span> <span>to
the brain</span></span><span> where
they are processed into the images we see. The answer is true. Animals
with photoreceptors have good vision.</span></span>