Use the maps below to answer the question.
Tree Defoliation Caused by Gypsy Moths
Maps courtesy of the U.S. Forest Service
The gypsy moth is a pest species whose larvae feed on the leaves of hardwood trees. The population size of gypsy moths naturally changes in cycles. As a result, the amount of defoliation caused by the moths also fluctuates. Which statement describes how the change in size of the gypsy moth population from 1972 to 1981 most likely affected the ecosystems represented by the maps?
A.
The plant species preferred by gypsy moths expanded to include shrubs and vines between 1972 and 1981.
B.
Animals that depend on hardwood trees for shelter increased in number between 1972 and 1981.
C.
Tree species that are not susceptible to gypsy moth defoliation decreased in number between 1972 and 1981.
D.
Other organisms that feed on the leaves of hardwood trees faced increased competition between 1972 and 1981.