A temperate deciduous forest is dominated by oak trees, which produce acorns. Populations of deer, black bear, and squirrels all rely on the acorns as a primary source of food. A large portion of the forest is cut down, causing it to lose most of its oak trees. What is most likely to happen in the forest as a result?

A.
Black bears, deer, and squirrels would undergo a mass extinction, so the forest's biodiversity would decrease.
B.
Deer would become less likely to survive and reproduce, so their population would decline.
C.
Squirrels would instantly adapt to the lack of acorns, so their population would remain stable.
D.
Black bears would benefit from the space made available by the loss of trees, so their population would increase.

By cutting the forest's oak trees and destroying it, the animals living in the forest, and especially the ones that are directly dependent on the oak trees and their acorns as primary source of food, will die out.

The squirrels will lose their primary and very possibly only food source. They are small creatures with very quick metabolism, so they need regular feeding. Once they are left without the acorns they will die out.

The deer will lose its basic and most important food, so the population will start to starve despite being able to feed on grasses. That will not be enough and the deer population will likely starve to death.

The black bear needs lot of food in order to gain as much fat as possible so that it can survive during the hibernation period. Once stripped from its most important food source, the black bear will manage to survive until the end of autumn because it is a very opportunistic eater, but that will not be enough so that the black bears manage to survive through the winter while hibernating, so they will die out in the winter months.