Correct Response: D. In general, gaining first-hand experience is a stronger motivator than second- hand experience. Therefore, having students work with a local group that tries to prevent and minimize environmentally harmful behaviors would be the most effective option for influencing students' actions in protecting the ecological health of their communities. Reading an article (A), writing an essay (B), or taking a tour (C) would be less effective, even though each of these activities is related to the environment, because none of these options require students to actively participate in activities that influence the ecological health of their communities.