The author's purpose in the passage about pet cloning, based on available context, could be to discuss the ethical and practical considerations of the process. Two sentences that suggest a critical view of pet cloning include experts disputing the possibility of creating exact replicas and claims about false promises by cloning companies.
The controversy of pet cloning has many dimensions including ethical, biological, and social implications. In the passage 'The Pet Cloning Controversy,' it is likely that the author's purpose is related to discussing these multifaceted aspects. Without the full passage, it's challenging to determine the specific stance of the author, but we can infer from context clues.
For instance, if the author emphasizes the joy that cloning brings to pet owners, they could be arguing in favor of cloning (Response A). Conversely, if they highlight the ethical concerns and technical challenges such as the high failure rate in cloning represented by the 277 attempts to produce Dolly the sheep, they may be arguing against it (Responses C or D).
Given the provided context, if the author discusses the unreliability of producing an exact genetic copy and the ethical concerns associated with this process, it helps to suggest a critical view of pet cloning. Sentences that reference the challenges or false promises of cloning, such as experts arguing against the possibility of true replicas (Sentence B) and highlighting the false claims of pet cloning companies (Sentence D), most helpfully suggest the author's purpose if it's indeed critical of pet cloning.