Which of the following statements are true with reference to homology…

The correct answer is Option (3) → (A), (B), (C) and (D)

Homologous organs have the same basic structure and origin but may do different jobs. They arise by divergent evolution.

(A) Homology indicates common ancestry. — Correct. A shared plan of structure means a shared ancestor from which the organs diverged.

(B) Whale and Cheetah share similarities in the pattern of the bones of the forelimbs. — Correct. The flipper of a whale and the leg of a cheetah do different jobs, but both have humerus, radius, ulna, carpals, metacarpals and phalanges.

(C) Vertebrate heart is an example of homologous organs. — Correct. The book gives vertebrate hearts and brains as further examples of homology.

(D) Thorn of Bougainvillea and tendrils of cucurbita represent homology. — Correct. Both are modified stems, one for protection and one for climbing.

NCERT Extract:
What Are the Evidences for Evolution? – “… Comparative anatomy and morphology shows similarities and differences among organisms of today and those that existed years ago. Such similarities can be interpreted to understand whether common ancestors were shared or not. 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. Other examples are vertebrate hearts or brains. In plants also, the thorn and tendrils of Bougainvillea and Cucurbita represent homology (Figure 6.3a).”

Figure 6.3 Example of homologous organs in (a) Plants and (b) Animals