【正确答案】：
MARK TWAIN IS KNOWN AS A LOCAL COLORIST, WHO PREFERRED TO PRESENT SOCIAL LIFE THROUGH PORTRAITS OF THE LOCAL CHARACTERS OF HIS REGIONS  , INCLUDING PEOPLE LIVING IN THAT AREA, THE LANDSCAPE, AND OTHER PECULIARITIES LIKE THE CUSTOMS, DIALECTS, COSTUMES AND SO ON. THE RICH MATERIAL OF HIS BOYHOOD EXPERIENCE ON THE MISSISSIPPI VALLEY AND THE WEST BECAME HIS MAJOR THEME . HE WROTE ABOUT THE LOWER-CLASS PEOPLE, AND USED LOCAL COLOR AND HISTORICAL SETTINGS TO ILLUSTRATE，AND SHED LIGHT ON THE CONTEMPORARY SOCIETY .
【题目解析】：本题考查马克·吐温小说中反映的地方色彩。马克吐温是一位著名的地方色彩学家，他更喜欢通过描绘他所在地区的当地人物，包括居住在该地区的人们、风景以及其他诸如风俗、方言、服饰等特点来展现社会生活。他童年时在密西西比河谷和西部的丰富经历成为他作品的主要主题。他描写了关于下层社会的文章，并用当地的色彩和历史背景来说明，并对当代社会进行了阐释。