(a) Our arm and a dog’s fore-leg.

(b) Our teeth and an elephant’s tusks.

(c) Potato and runners of grass.

(d) All of the above.

Solution:

The correct answer is (d).

Homologous organs have the same origin as the organs listed above, but they have different roles. Homologous organs are organs from different species that have a similar fundamental structure but perform diverse tasks. The flippers of a whale, the forelimbs of a frog, and the forelimbs of a man, for example, all have the same fundamental anatomy but perform different roles, which is why they are referred to as homologous organs.