Question: The James River provides the main drainage between two plateau regions, the large plateau on the eastern side and which other plateau?

The Cumberland Plateau is the southern part of the Appalachian Plateau in the Appalachian Mountains of the United States.  It includes much of eastern Kentucky and Tennessee, and portions of northern Alabama and northwest Georgia.  The terms "Allegheny Plateau" and the "Cumberland Plateau" both refer to the dissected plateau lands lying west of the main Appalachian Mountains.  The terms stem from historical usage rather than geological difference, so there is no strict dividing line between the two.  Two major rivers share the names of the plateaus, with the Allegheny River rising in the Allegheny Plateau and the Cumberland River rising in the Cumberland Plateau in Harlan County, Kentucky. <SEP> The James River (also known as the Jim River or the Dakota River) is a tributary of the Missouri River, approximately 710 miles (1,140 km) long, draining an area of 20,653 square miles (53,490 km) in the U.S. states of North Dakota and South Dakota.  About 70 percent of the drainage area is in South Dakota.  The river provides the main drainage of the flat lowland area of the Dakotas between the two plateau regions known as the Coteau du Missouri and the Coteau des Prairies.  This narrow area was formed by the James lobe of the Laurentide Ice Sheet during the last ice age, and as a consequence the watershed of the river is slender and it has few major tributaries for a river of its length. <SEP> The McGregor Plateau is a sub-plateau of the Fraser Plateau, the northernmost major subdivision of the Interior Plateau spanning the inland regions of the Pacific Northwest.  Located in British Columbia, Canada, to the east of the city of Prince George, British Columbia, the McGregor Plateau lies between the main spine of the Northern Rocky Mountains on the east and the Fraser River on the west, beginning on its southeast at the confluence of the Torpy River with the Fraser and running northwest, parallel to the Fraser and the Rockies, to end in the area of the Arctic and Pacific Lakes to the north of the great bend in the Fraser River just upstream from and to the northeast of Prince George.  The McGregor Plateau is very mountainous in character and includes several large rivers, the largest being the McGregor River and Herrick Creek.  Included in the McGregor Plateau is the McGregor Range, which lies between the McGregor and Torpy Rivers. <SEP> The Coteau du Missouri, or Missouri Plateau, is a large plateau that stretches along the eastern side of the valley of the Missouri River in central North Dakota and north-central South Dakota in the United States.  In the Canadian provinces of Saskatchewan and Alberta this physiographic region is classified as the uplands Missouri Coteau which is a part of the Great Plains Province or Alberta Plateau Region which extends across the south west corner of the province of Saskatchewan as well as the south east corner of the province of Alberta.  Historically, in Canada the area was known as the Palliser's Triangle regarded as an extension of the "Great American Desert" and unsuitable for agriculture and thus designated by Canadian geographer and explorer John Palliser.  The terrain of the Missouri Coteau features low hummocky, undulating, rolling hills, potholes, and grasslands.