Okay. Conservation is saving something, consternation is feeling anxiety, environmentalism is concern for the environment, and consumerism has to do with economics. B and D are out, because they do not work in this problem. Turning off lights and TVs off when unused is saving energy. Environmentalism seems to work, because you're using less and you're helping the environment, but the best word here is conservation. You are saving energy and that has to do with energy conservation. The answer is A: conservation.
