It illustrates the cycling of matter, just like in a natural ecosystem.
Option D.
<h3><u>Explanation:</u></h3>
The natural stable ecosystem is defined as the ecosystem which has the members doing their part of job and each and every member contribute to the stability of the ecosystem by completing food chains.
Here in this bottle ecosystem the boy put the stones, rocks, water which gives proper nutrition to the growing plants and animals which are also introduced by the boy. The plants produce oxygen and consume carbon dioxide whereas the animals consume oxygen and produce carbon dioxide. Thus the cycle is maintained and stability is achieved.
Well, the word medicine is the general synonym of antibiotic - they mean the same thing.
The same general processes occur in meiosis and mitosis