The correct answer is Mark Twain, pseudonym of Samuel Langhorne Clemens (1835-1910). Twain was an American writer exponent of American Literary Realism, because in his works he depicted social realities and the lives, everyday activities, and experiences of ordinary people. Today he is considered one of America's best-known novelists, whose writings, such as The Adventures of Huckleberry Finn (1885) and The Prince and the Pauper (1881), reveal to the reader the reality of 19th-century life in a changing America.