Hint: Change in characteristics over generations, and the introduction of inheritable characteristics over generations and over-time is known as evolution. Tracing the evolutionary history helps in identifying the relations with generations, and how species can have a common ancestor.
The organs which have the same function, but have a different ancestral origin are known as Analogous organs. The wings of insects and birds are examples of analogous organs, since they have the same function, which is flying but the two organs have different origins. The wings of insects arise from the inner or outer surface of the body whereas the wings of birds are modified forelimbs. These organs do not show a common lineage. Another example of analogous organs are the sugar gliders and flying kangaroos where the flying appendages have different arrangements.
Considering the other given options:
Vestigial organs are those which have lost its functionality with the process of evolution. These organs have had functions in the ancestral generations. The example of a vestigial organ is the Vermiform Appendix present in Human Beings.
Homologous organs are those which have a common ancestry or lineage, while they are evolved to perform different functions. The examples of homologous organs are the forelimbs of various mammals such as man, cheetah, whale and bat, where all of it has a different function, but has a common arrangement of bones. This can represent the presence of a common ancestor.
Hence, the correct answer is option (A)
Note: The process of evolution can be traced through different evolutionary pieces of evidence. It can be done by assessing the basic anatomy of the organisms (the concept of homologous organs), examining the fossil records, as well as observation in the molecular levels, such as DNA examination, and also by examining the biogeography of the organisms.