Which one of the following correctly describes homologous organs?

Homologous organs often have different functions but are structurally similar because of common ancestry. For example, the forelimbs of vertebrates such as humans, bats, whales, and birds are homologous organs. Although these forelimbs have different functions in different organisms, they share a similar structure and origin, with the same bones arranged in a similar pattern. This suggests that they evolved from a common ancestor with a similar forelimb structure and that over time, natural selection led to the divergence in function among different species.
Structurally different organs that have evolved to perform similar function are termed analogous organs.
Vestigial organs are the non-functional organs of a species that were functional in the ancestor. 
Organs that suddenly appear in an organism after a period of absence are atavistic organs.