The introduction of a predator population of arctic foxes to a small island caused the grassland community of the island to slowly convert to tundra due to changes in nutrient cycling. Which of the following best explains this change in the ecosystem?

A) The grassland habitats were negatively affected by the trampling and burrow-digging of the predator population.
B) The water intake of the predator population reduced water availability for grasses.
C) The predator population consumed a large proportion of the grass-like plants.
D) The predators consumed an herbivore or secondary consumer population that was promoting grass-like habitats.