Answer:
The answer is C. Snakes evolved from the same common ancestor as species in which these structures are functional.
Step-by-step explanation:
The organs which apparently have no functional role in an organism but thought to be functional in past are called Vestigial Organs. One common example is the non functional Pelvis and hind Limbs in snakes. It is thought that snakes have evolved from reptiles. From fossil record it was predicted that many snakes like species were present in past and they had the pelvic bones while due to adaptation to the changing environment they lost the functional bones and evolved as snakes.