Hint: In living beings various organs of their body get modified to make them survive according to given conditions. These modifications lead to the origin of new species.
A. Analogous organs – They are not anatomically similar structures though they perform similar functions. Analogous organs are a result of convergent evolution. We can say that similar habitat has resulted in selection of similar adaptive features in different groups of organisms but towards the same function.
B. Homologous organs – Forelimbs of man, cat, bat and whale are homologous organs. These organs have the same anatomy and origin but they perform different functions for limbs of man, cat, bat and whale have humerus, radius, ulna, carpals, metacarpals and phalanges i.e. similar anatomy but they perform different functions. In these animals, the same structure developed along different directions due to adaptation to different. This is divergent evolution.
C. Missing link- The fossil organisms which show characters of two different groups of animals are called the missing link.
D. Fossil- Fossils are formed when the dead animals of these a or large takes and of the land carried to the sea or large takes by rivers sink down and get buried in the rocks deep under the earth. Due to absence of oxygen high temperature and pressure, fossils formed.
So, the correct option is (B).
Note: In the course of evolution living beings acquire some specific characters and these characters get inherited from one generation to another. This finally leads to the origin of new species with specific modifications in their body. These modifications make them survive in nature.