Answer:
2: Vestigial Structure
Step-by-step explanation:
A vestigial structure refers to a body part or organ that has lost its original function or has become greatly reduced in size or usefulness during the course of evolution. These structures are remnants of ancestral traits that were once functional but have gradually lost their purpose as the organism evolved and adapted to changing environments.
Vestigial structures can be found in various organisms, including humans. Examples in humans include the appendix, tailbone (coccyx), and wisdom teeth. These structures were more functional in our evolutionary ancestors but have lost their original purpose in modern humans.
The presence of vestigial structures provides evidence for the theory of evolution, as they reflect the evolutionary history and gradual changes in organisms over time. These structures may still serve minor or secondary functions, or they may have no significant function at all.