Final answer:
The central idea of the excerpt revolves around a goatherd wanting to expand his herd by integrating wild goats, which is a common practice within pastoral societies to sustain their livelihoods.
Step-by-step explanation:
The central idea of the excerpt from "The goatherd and the wild goats" best aligns with option (A) The goatherd wants the wild goats to join his herd. The provided text descriptions about pastoral societies illustrate how herders, such as Bedouins, rely on the herding of animals, including goats, for survival. These societies have developed extensive knowledge of animal behavior and the environment to sustainably manage their herds. They strategically engage in practices like animal domestication and transhumance—moving herds to fresh pastures—to maximize the use of resources and ensure the health and productivity of their livestock. Through these strategic methods, the herders not only survive but maintain the well-being of their herds. Therefore, the goatherd's motive to have wild goats join their herd aligns with the central theme of maximizing herd potential and supporting pastoral livelihoods.