Which of the Following Does Sober See as an Important

Which of the following does Sober see as an important reason for environmentalists to resist simply grounding their ethics in what is "natural?"

A) If we are part of nature, then everything we do is natural, including destroying the environment.
B) Domesticated species have as much right to protection as wild or "natural" ones.
C) The appeal to nature easily leads to a melancholy and sobering attitude toward existence.
D) Appeals to nature tend to rest on an insufficiently critical embrace of post-Darwinian biology.