Grazing is a method of feeding in which herbivores, such as sheep, feed on plants. The intensity in which the herbivores in an ecosystem graze impacts the biodiversity of the plants in that ecosystem, as shown in the graph below. According to the graph, biodiversity is low during low grazing intensities. This is because only a few species of plants are able to outcompete the others and dominate the ecosystem. As the grazing intensity increases, the biodiversity increases because the dominant plant species are kept in check by the grazers. This allows the weaker competitors to grow. At very high grazing intensities the biodiversity decreases because only plants with adaptations to tolerate the effects of grazing are able to survive.

Which of the following best explains how plant biodiversity would change if all of the grazers were suddenly removed from an ecosystem experiencing high intensity grazing?
A.
Plant biodiversity would likely decrease because every species of plant could grow without limitation after the herbivores were removed.
B.
Plant biodiversity would likely increase because removing one population from an ecosystem would allow more resources for all the others.
C.
Plant biodiversity would likely decrease because a few of the more dominant plant species would outcompete all the others.
D.
Plant biodiversity would likely increase because only a few of the remaining plant species would be able to thrive without the herbivores.