An example of homeostasis in living organisms is

A.

cooling effect resulting from evaporation of water from the body surface

B.

root hairs of a plant growing towards the source of light

C.

changing of the body colour of chameleon to match the colour of the foliage on which it is resting

D.

the release of phosphorus into the phloem of a plant growing in a phosphorus-deficient soil

Correct answer is D

Homeostasis is a living organism's way of maintaining a stable internal environment even in the event of external environmental changes. When the plant keeps supplying phosphorus to the phloem even in the case of a deficiency in the soil, it maintains a steady balance on its inside irrespective of the lack in the soil.