Answer:
D) The disappearance of a keystone species due to an increase in water temperature.
Step-by-step explanation:
A) A decrease in fishing throughout the Great Lakes region. B) A slowdown of clear cutting and construction in the area. C) Normal snowfall in winter, ensuring that water levels remain normal. D) The disappearance of a keystone species due to an increase in water temperature.
The answer would be the disappearance of a keystone species due to an increase in water temperature.
When an ecosystem is said to be stable, it means that the communities of organisms in that ecosystem are relatively undisturbed/unchanged.
The stability of an ecosystem depends largely on the different communities of plant and animal species in interacting with the non-living components of the environment. Hence, when keystone species disappear due to increase in the temperature of the water, the various biological processes are disrupted and the stability of the ecosystem becomes threatened.
Decrease in fishing, slowdown of clear cutting and construction in the area and normal snowfall that ensures normal water levels all serve to promote the stability of the ecosystem.
The correct option is D.