Hemlock woolly adelgid is an insect pest to hemlock trees. it was introduced in the united states during the 1920's. it is not native to the united states and has few natural predators. to control this insect pest, scientists identified a species of predatory beetle, (pseudoscymnus tsugae). they hope to introduce this beetle to areas where the woolly adelgid is destructive, reduce the woolly adelgid population, and minimize the damage caused to hemlock trees. which of these questions best summarizes the research described? a) are hemlock trees important to the ecosystem? b) how does the woolly adelgid kill hemlock trees? c) can insect pests be used to control damaging predators in sensitive environments? d) can predatory beetles reduce environmental damage caused by the woolly adelgid?