The correct response is: It sets up a contrast between Buck’s comfortable life and the harsh conditions in the wild, highlighting the conflict he faces.
This choice emphasizes the significant transition Buck undergoes from a life of comfort and luxury in California to the brutal realities of the Yukon wilderness. This contrast is crucial to the narrative as it sets the stage for Buck's development and the challenges he encounters, reinforcing the theme of survival and the primal instincts that emerge within him.