Solution

The coxal gland is a gland found in some of the arthropods and arachnids. The gland is involved in excretory function. The gland is composed of pair of excretory organs. There is an end sac which is responsible for the collection of urine. These glands are responsible for collecting the wastes and then excreting in the form of urine. They are found in all arachnids. They are also found in other chelicerates.
Thus, the correct answer is option D.