The correct answer is C. Redundant organs present in an organism, which have been functional in the organism’s ancestors
Explanation:
An organ or any other biological structure is categorized as "vestigial" if the organ or structure is no longer functional, which means it does not have a purpose in the present but it had a purpose in past lineages or the organism's ancestors. For example, in modern humans, the coccyx (bone at the end of the vertebral column) is considered as a redundant and vestigial structure because in the human ancestor's this acted as a tailbone but nowadays due to evolution humans lack of a tail, and therefore this bone has lost its function. According to this, vestigial organs can be defined as "Redundant organs present in an organism, which have been functional in the organism’s ancestors".
