The forelimbs of bat, whale, cheetah and human are the examples of:

The correct answer is Option (3) → Divergent evolution and homologous organs

The forelimbs of whales, bats, cheetahs and humans have the same bones (humerus, radius, ulna, carpals, metacarpals, phalanges) but do different jobs. They are homologous organs, formed by divergent evolution.

Option (1) Divergent evolution and analogous organs — Incorrect. The forelimbs of bat, whale, cheetah and human have the same basic bone structure but do different jobs, so they are homologous, not analogous. Analogous organs, like the wings of a butterfly and a bird, have different structures but the same function.

Option (2) Convergent evolution and analogous organs — Incorrect. Convergent evolution does give analogous organs, but these forelimbs are not analogous. They share one structural plan from a common ancestor and have diverged in function, which is divergent evolution.

Option (3) Divergent evolution and homologous organs — Correct. The forelimbs of bat, whale, cheetah and human have the same basic structure (the same bones) but do different jobs. Organs like these are homologous, and the process that gives them is divergent evolution: one ancestral structure changing in different directions.

Option (4) Convergent evolution and homologous organs — Incorrect. The forelimbs are homologous, but homology comes from divergent evolution, where one ancestral structure is modified for different needs. Convergent evolution brings unrelated structures to a similar function, giving analogy.

NCERT Extract:
What Are the Evidences for Evolution? – “… For example whales, bats, Cheetah and human (all mammals) share similarities in the pattern of bones of forelimbs (Figure 6.3b). Though these forelimbs perform different functions in these animals, they have similar anatomical structure – all of them have humerus, radius, ulna, carpals, metacarpals and phalanges in their forelimbs. Hence, in these animals, the same structure developed along different directions due to adaptations to different needs. This is divergent evolution and these structures are homologous. Homology indicates common ancestry.”