Complete question:
Which of the following pairs represent homologous structures?
Answer:
3. Forelimbs of a bat and forelegs of a horse
Explanation:
Homologous characters are structures with the same basic elements. Their position in the body and the relations with adjacent structures are also the same in different organisms, and they even share the same embryological development.
These structures might show variations between the organisms exhibiting them. Variations might be related to their function and to the environment in which the organism lives. The function they accomplish is not necessarily the same in all the organisms involved.
These homologous characters are present in organisms related that share a common ancestor.
For example, whales, humans, and cats all have the same bones in the same order, but they matured differently in later embryological development.
Among the options, the only possible pair that represents homologous characters is option 3. Forelimbs of a bat and forelegs of a horse. Both structures are the anterior extremities of the animals and share the same bones, even though they might differ in the development degree. Forelimbs and forelegs have the same position and relation with other structures in the body, and embryologically, they are the same.
