Why is E incorrect?

Hello @xDaltonLaney, E demonstrates that the crayfish do not totally depend on the dragonfly larvae as a food source. However, it is a bit of a stretch to assume that this balances the ecosystem. Try to stick with the information given in the passage. Also, notice that E says "if the local population of Hine's emerald dragonflies dies out." We are trying to explain why dragonfly populations are healthier where they coexist with crayfish. A condition that occurs when the dragonflies are all dead doesn't explain this. A is a better choice because it shows how the crayfish, though predators, also have a positive effect on dragonfly populations. They dig chambers filled with water, thus creating more habitat in which the larvae can survive.