The correct answers are B. Ouachita Mountains and D. Red River Plains
Step-by-step explanation:
Oklahoma is a state of the United States located at the South center of it. In terms of geography, this state is characterized by being located mainly on the Great Plains, although part of it has a mountainous terrain, this can be explained as the Ouachita Mountains, the Ozark Mountains, and others cross the state. Indeed, in the case of the Ouachita Mountains, this cover part of Oklahoma in the Southeast. Besides this, as one fo the borders of Oklahoma is part of the Red River, in this state one region belongs to the Red River Plains.