Use the Following Diagram from the Text Showing the Spread

Multiple Choice

Use the following diagram from the text showing the spread of the cattle egret, Bulbulcus ibis, since its arrival in the New World, to answer the following question.

Figure 52.1
-Experts in deer ecology generally agree that population sizes of deer that live in temperate climates are limited by winter snow. The deer congregate in "yarding" areas under evergreen trees because venturing out to feed in winter is energetically too expensive when snowfall depths accumulate to above 40 cm. Deer often stay yarded until the spring thaw. Snow depth over 40 inches for more than 60 days results in high mortality due to starvation. This observation best illustrates which of the following principles about factors that limit distribution of organisms?

A) Abiotic factors, such as weather extremes, ultimately limit distribution.
B) Organisms will face extinction unless they adapt to conditions or evolve new mechanisms for survival.
C) Environmental factors are limiting not only in amount but also in longevity.
D) Daily accumulations in snow depth gradually add up to cause increased deer mortality.
E) Temporary extremes in weather conditions usually result in high mortality in the deer population.