Which of the following is a defining property of living organisms?

 Defining property of living organisms is the one exhibited by all living organisms without any exception and at the same time not exhibited by any non-living objects.

Growth is also shown by non-living objects, e.g., mountains grow by the accumulation of materials over their surfaces.

Ability to make sound is not seen in all living organisms.

Some living organisms do not reproduce like infertile human couples, worker honey bees, mules, etc.

Response to external stimuli (consciousness) is seen in all living organisms without any exception and therefore it is the defining property of living organisms.