If the deer population increases, this would lead to increased grazing on the grass, which is a primary food source for the deer. As a result, the grass population would likely decrease due to overgrazing.
Consequently, a decrease in the availability of grass could eventually lead to a decrease in the deer population, which would then impact the lion population. Here's a breakdown of the potential consequences:
- The plant population would increase. (This is incorrect; the grass population is likely to decrease due to increased deer grazing.)
- The lion population would stay the same. (This is unlikely, as changes in deer population can eventually affect lion population dynamics.)
- The plant population would decrease. (This is likely true due to overgrazing by the increased deer population.)
- The lion population would decrease. (This could happen eventually if the deer population decreases due to lack of food.)
Given that the question asks for the consequences of the deer population increasing, the most accurate answer would be:
The plant population would decrease.