Final answer:
The process in which arthropods shed their exoskeleton to allow for growth is known as molting. Molting is necessary because the non-growing exoskeleton must be replaced to accommodate increasing body size, and is followed by ecdysis. The correct answer to the question is option b. Molting.
Step-by-step explanation:
The process which culminates with arthropods regularly shedding their exoskeleton because it has become too small for the growing body is called molting.
Arthropods, as members of the superphylum Ecdysozoa, possess an exoskeleton made primarily of chitin, sometimes biomineralized with calcium carbonate. This protective layer prevents water loss, offers support and defense against predators, and functions as an anchor for muscle attachment. However, the exoskeleton does not grow with the animal and must be periodically shed to allow for growth. During this critical stage, arthropods are at their most vulnerable as they wait for their new exoskeleton to harden.
The process of shedding the old exoskeleton is known as molting. Molting is followed by ecdysis, the actual act of removing the old exoskeletal layer. This physiological necessity enables arthropods to grow and adapt to environmental pressures, leading to significant diversification in size and morphology among the species. It is a limitation on the animal's size, as significant increase in the exoskeleton's thickness is required to support additional weight.
While molting is a regular part of an arthropod's life cycle, it is distinct from metamorphosis, another developmental process through which certain organisms like insects undergo a complete transformation from larval to adult forms. Therefore, the correct option for this question is b. Molting.