Which of the following are examples of nonnative species disrupting ecosystems? 1) The number of frogs decreases after a species of toad is brought in to control insects. 2) Trees used to control soil loss begin to spread over large areas, killing other trees. 3) Rain containing chemicals falls on an area and damages a large part of a forest. A. 3 only B. 1 and 2 C. 1, 2 and 3 D. 1 only