Coxal glands are the excretory organs of

A. Crayfish

B. Devilfish

C. Jellyfish

D. Arachnid

Arachnida is a class within the phylum Arthropoda. These animals excrete waste through coxal glands, which are paired sacs that collect and store waste materials. The urine exits the sac through an opening called the coxa. Common examples of Arachnida include spiders, scorpions, mites, and ticks.

All arthropods have jointed appendages. Within this phylum, the class Insecta includes animals with three pairs of legs. Their sensory organs include eyes, antennae, and statocysts. Examples of insects are beetles, flies, dragonflies, and cockroaches.

Arthropods are covered with a chitinous exoskeleton, which provides protection and support. This exoskeleton is periodically shed and renewed through a process called moulting or ecdysis, allowing the body to grow and expand. The exoskeleton is made of chitin, reinforced with proteins, calcium carbonate, and calcium phosphate, which make it hard and durable.

Hence, the correct answer is option D.