Final answer:
The excerpt that supports the novel's theme of alienation and loneliness is when Montag is ostracized from society and his family shuns him, leading to a lonely life.
Step-by-step explanation:
The excerpt that supports the novel's theme of alienation and loneliness is B) After deciding to not be a fireman anymore, Montag is ostracized from society and his family shuns him. This leaves him to live a lonely life. The excerpt that best supports the novel's theme of alienation and loneliness is option B) After deciding to not be a fireman anymore, Montag is ostracized from society and his family shuns him. This leaves him to live a lonely life. This option directly addresses both themes by describing Montag's ostracization from society and his family, which results in him living a life of solitude. The mention of Montag's decision to leave his role as a fireman, which isolates him from his community and leads to loneliness, aligns with the examined themes in literary nonfiction works that explore solitary life away from societal norms.