Question

An example of homologous organs is

(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.

Answer 1

(b)An example of homologous organs is all of the above.
Homologous organs are organs which are similar in structure and origin but have different functions in different organisms. Our arms and a dog's forelegs have same structure but perform different functions. Similarly our teeth and the tusks of elephants are similar in origin but perform different functions. Also potato and runners of grass are stem modifications. Hence, all the options are examples of homologous organs.