What is the writing style of Mark Twain?

What is the writing style of Mark Twain?
【正确答案】：A. Mark Twain is known as a local colorist. He presents social life through portraits of the local characters of his regions, including people living in that area, the landscape, and other peculiarities.
B. Another fact that made Mark Twain unique is his magic power with language, his use of vernacular.
C. He used the colloquialism to cast his protagonists in their everyday life. His characters speak with a strong accent. Different characters from different literary or cultural backgrounds talk differently.
D. His humor is remarkable.