NCERT Question 2 - Chapter 9 Class 10 - Heredity and Evolution

An example of homologous organs is

1. our arm and a dog’s foreleg.
2. our teeth and an elephant’s tusks.
3. potato and runners of grass.
4. all of the above.

Answer:

These organs have the same origin but serve different functions .

For Example - 

1. The structure of our arm and a dog's foreleg is similar , but while our arm works to lift things , a dog’s foreleg is used to walk, stride and run .
2. Human teeth are used to chew and grind food , elephant tusks are used for digging, resting their trunks and other such activities.
3. Both potatoes and Runners of Grass represent the stem part of a plant but have different functions .

This means they have all evolved differently from a common ancestor . 

This is known as Homologous Organs or Divergent Evolution . 

So, the answer is, (d) all of the above