Answer:
Specitation increases biodiversity, while extinctions decrease biodiversity.
Explanation:
Biodiversity is the variety of life on Earth or some specified geographic area of the planet; the diversity of life occurs at the genetic level, at the species level, at the ecosystem level, and in evolutionary lineages.
There are exchanges that happen continuously in our bodies. One exchange is the gas exchange, or respiratory, system. This is the system where carbon dioxide is released from the lungs into the air, and oxygen is taken into the lungs from the air. This exchange happens in the air sacs of the lungs called the alveoli.
All planets have these same layers (From deepest to shallowest, inner core then the outer core, then the mantle, and lastly the crust. A good example is the Earth) that is shown in the diagram, even the sun has all the layers I just listed.
But, some planets I can think of are Mars, Venus, Moon, and the Earth of course.
Layer C. sounds like it could also represent Layer D, since they are so close.
P. S. I did my best to try to answer this.