Final answer:
The best statement of Berger's essay's purpose is to explore the dual role of animals as symbols and beneficiaries in international diplomacy.
Step-by-step explanation:
The sentence that best states the purpose of Berger's essay is C: to show how animals can be both symbols and beneficiaries of international diplomacy. This aligns with the themes discussed in John Berger's essay 'Why Look at Animals?', where he explores the role of animals in human imagination beyond mere resources like meat or leather, suggesting animals enter the human imagination as 'messengers and promises.' This broader view of animals considers their symbolic significance as well as their physical well-being in the context of human-animal relationships and international policies.