Answer:
- For the first statement: An ecosystem with populations that mate with unrelated species.
The ecosystem will more stable. The mating with unrelated specie will create the ability to cop with any disaster and the chances of extinction of any specie will become very less.
- For the second statement: an ecosystem that has very few species at every trophic level.
Less stable.
An ecosystem which has a very low number of species ins not so stable because of less biodiversity. Biodiversity is directly proportional to the stability of the specie.
- For the third statement: An ecosystem with populations that mate with only related species.
Less stable.
The specie which does not have the ability to mate with unrelated specie makes an unstable ecosystem. Because if any thing happens to the ecosystem like climate change, that specie will unable to evolve and go extinct immediately.
- For the fourth statement: An ecosystem that has many species at every trophic level .
More stable:
The ecosystem having a large number of biodiversity at each trophic level leads to a stable an ecosystem. Because biodiversity is directly proportional to the stability of the specie.