Final answer:
The theme of 'The King of Mazy May' by Jack London revolves around courage, integrity, and resourcefulness in adversity, reflecting London's common focus on survival and ethical struggle in his literary works.
Step-by-step explanation:
The theme in an excerpt of 'The King of Mazy May' by Jack London is best represented by an understanding of the conflict presented within the narrative. As the character in the story, Walt Masters, faces the challenge of standing up against claim jumpers, the overarching theme points to the importance of courage, integrity, and resourcefulness in the face of adversities. These adversities often come in the form of the harsh environment or immoral characters, emphasizing a typical London theme: the struggle for survival, be it against nature or human corruption. This aligns with London's recurring fascination with the rawness of the natural world and the ethic of survival, seen in his other works such as 'To Build a Fire' and 'Call of the Wild'.