Final answer:
Missouri is the state with both the southern Ozark Mountains and the St. Francios Mountains, areas of significant geographical and historical interest.
Step-by-step explanation:
The state that contains both the Ozark Mountains in the southern part and the St. Francios Mountains is Missouri. The Ozark Mountains are a significant physiographic region located primarily in northern Arkansas and southern Missouri. The St. Francios Mountains are an ancient mountain range within the Ozarks, situated in southeastern Missouri. This region marked a notable moment in the United States history during the debate over Missouri's admission to the Union, which was entangled with issues surrounding slavery and sectional conflicts as highlighted by the Missouri Compromise, which allowed certain territories including Missouri to practice slavery while being an exception to the rule that slavery was forbidden north of latitude 36° 30'. Missouri's rich geological features and historical context provide an important window into both the physical landscape and the political climate of early 19th century America.