Ok so take any plant in for say a forest for example. If a certain plant dies an animal wont be able to feed off of it . If that animal only eats that plant, it's gonna die off starvation. That species in that ecosystem would be no more. If all the water evaporated in a lake then all the fish would die and the animals in the forest would need to find something else to drink out of.
The best answer is D. Mexico
It contracts hope that helps
Kingdom Fungi
Because it can reproduce asexually while the others don’t
Hope this helps ʕ•ᴥ•ʔ