Which of the following does David Orr (1993) say about sustainability? (multiple answers) Group of answer choices "We cannot know what sustainability means until we have decided what we intend to sustain and how we propose to do so." "We must choose along the continuum that runs between biophilia and biophobia, intimacy or mastery" "Humans are fundamentally selfish and destructive. Therefore, the best path to sustainability is to reduce our numbers drastically." "Sustainability primarily requires a far more efficient use of natural resources