Answer:
The correct answer would be B. a coastal region with three ecosystems, each of which supports many different species
Biodiversity refers to the sum up of all the variety or type of species of living organisms inhabiting a particular area.
It includes all living organisms whether plant, animal, insect, or bacteria.
The more the variety of living organisms present in an area the more would be its biodiversity.
Similarly, the coastal region has three types ecosystem each of which supports different types of species.
Thus, this region would have the most variety of organisms.
Hence, it would have maximum biodiversity as compared to the other regions.