Final answer:
The statement that best captures the central idea is that Mark Twain's early experiences influenced his writing style, as evidenced by his use of dialect, regional humor, and satirical views on societal norms, including slavery and corruption.
Step-by-step explanation:
The statement that best expresses the central idea of the passage from "Mark Twain’s First Appearance" would be Option B: Mark Twain's early experiences influenced his writing style. This is supported by details in the provided information, which highlight how Twain's use of dialect, regional humor, and satire is derived from and reflects the broader character of American life in his era, especially the pre-Civil War South and the West. His literature, characterized by these elements, depicts social realities and the human condition, thus providing critical commentary on the societal norms of the time, including slavery and corruption.
Twain's works, including The Adventures of Huckleberry Finn and The Gilded Age, are rich with realism, portraying both the pioneering spirit and the prevalent issues of the day. Through his detailed first-person narratives, he brings an authentic voice to American Realism in literature. This narrative style, along with his humor and critique, effectively influenced the identities and beliefs of his readers, which is why he is remembered as a significant figure in American literary history.