An increase in the available water in an ecosystem would increase the sustainability of an ecosystem.
An increase of human interference can negatively impact local flora and fauna populations.
A decrease in the amount of sunlight would negative impact plants.
A decrease in the number of available producers will negatively impact the entire food chain/food web.
It is the same as creating more pests or setting up dominant species which upset the ecological food pyramid leading to decimation of trophic levels or predators and energy cycling. Fishes feed on microscopic algae and animals the primary base of the food chain in water, if they are not checked they will choke the rivers and oceans causing toxic waters. Fish feed to contain them, in the process they grow and increase in numbers but their population is checked by bigger fishes and so on till it reaches a top predator which is usually a large animal.
The answer to this question is C. Cornea
The second image went through permineralization
Heart, lungs, arteries, veins,cells, etc.